* [PATCHv6 bpf-next 01/29] ftrace: Add ftrace_hash_count function
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 12:37 ` bot+bpf-ci
2026-05-27 11:39 ` [PATCHv6 bpf-next 02/29] ftrace: Add ftrace_hash_remove function Jiri Olsa
` (27 subsequent siblings)
28 siblings, 1 reply; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding external ftrace_hash_count function so we could get hash
count outside of ftrace object.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/ftrace.h | 2 ++
kernel/trace/ftrace.c | 7 ++++++-
2 files changed, 8 insertions(+), 1 deletion(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 28b30c6f1031..282da661f131 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -551,6 +551,8 @@ int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, b
void ftrace_stub_direct_tramp(void);
+unsigned long ftrace_hash_count(struct ftrace_hash *hash);
+
#else
struct ftrace_ops;
static inline unsigned long ftrace_find_rec_direct(unsigned long ip)
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index b2611de3f594..57ab01fd00bd 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -6288,11 +6288,16 @@ int modify_ftrace_direct(struct ftrace_ops *ops, unsigned long addr)
}
EXPORT_SYMBOL_GPL(modify_ftrace_direct);
-static unsigned long hash_count(struct ftrace_hash *hash)
+static inline unsigned long hash_count(struct ftrace_hash *hash)
{
return hash ? hash->count : 0;
}
+unsigned long ftrace_hash_count(struct ftrace_hash *hash)
+{
+ return hash_count(hash);
+}
+
/**
* hash_add - adds two struct ftrace_hash and returns the result
* @a: struct ftrace_hash object
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* Re: [PATCHv6 bpf-next 01/29] ftrace: Add ftrace_hash_count function
2026-05-27 11:39 ` [PATCHv6 bpf-next 01/29] ftrace: Add ftrace_hash_count function Jiri Olsa
@ 2026-05-27 12:37 ` bot+bpf-ci
0 siblings, 0 replies; 34+ messages in thread
From: bot+bpf-ci @ 2026-05-27 12:37 UTC (permalink / raw)
To: jolsa, ast, daniel, andrii
Cc: bpf, linux-trace-kernel, kafai, eddyz87, songliubraving, yhs,
menglong8.dong, rostedt, ast, andrii, daniel, martin.lau, eddyz87,
yonghong.song, clm, ihor.solodrai
[-- Attachment #1: Type: text/plain, Size: 1087 bytes --]
> diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
> index 28b30c6f1031..282da661f131 100644
> --- a/include/linux/ftrace.h
> +++ b/include/linux/ftrace.h
> @@ -551,6 +551,8 @@ int update_ftrace_direct_mod(struct ftrace_ops *ops, struct ftrace_hash *hash, b
>
> void ftrace_stub_direct_tramp(void);
>
> +unsigned long ftrace_hash_count(struct ftrace_hash *hash);
> +
> #else
> struct ftrace_ops;
> static inline unsigned long ftrace_find_rec_direct(unsigned long ip)
Is a fallback stub needed here? The function is declared under
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS but other direct call functions in
this header provide static inline fallbacks in the #else block. If an external
caller uses this function on a kernel configured without direct calls, would
this cause a build failure due to an implicit declaration?
[ ... ]
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26509800686
^ permalink raw reply [flat|nested] 34+ messages in thread
* [PATCHv6 bpf-next 02/29] ftrace: Add ftrace_hash_remove function
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 01/29] ftrace: Add ftrace_hash_count function Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 03/29] ftrace: Add add_ftrace_hash_entry function Jiri Olsa
` (26 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding ftrace_hash_remove function that removes all entries
from struct ftrace_hash object without freeing them.
It will be used in following changes where entries are allocated
as part of another structure and are free-ed separately.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/ftrace.h | 1 +
kernel/trace/ftrace.c | 19 +++++++++++++++++++
2 files changed, 20 insertions(+)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index 282da661f131..d3acfac4f8a7 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -415,6 +415,7 @@ struct ftrace_hash *alloc_ftrace_hash(int size_bits);
void free_ftrace_hash(struct ftrace_hash *hash);
struct ftrace_func_entry *add_ftrace_hash_entry_direct(struct ftrace_hash *hash,
unsigned long ip, unsigned long direct);
+void ftrace_hash_remove(struct ftrace_hash *hash);
/* The hash used to know what functions callbacks trace */
struct ftrace_ops_hash {
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 57ab01fd00bd..45548b0200eb 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1249,6 +1249,25 @@ remove_hash_entry(struct ftrace_hash *hash,
hash->count--;
}
+void ftrace_hash_remove(struct ftrace_hash *hash)
+{
+ struct ftrace_func_entry *entry;
+ struct hlist_head *hhd;
+ struct hlist_node *tn;
+ int size;
+ int i;
+
+ if (!hash || !hash->count)
+ return;
+ size = 1 << hash->size_bits;
+ for (i = 0; i < size; i++) {
+ hhd = &hash->buckets[i];
+ hlist_for_each_entry_safe(entry, tn, hhd, hlist)
+ remove_hash_entry(hash, entry);
+ }
+ FTRACE_WARN_ON(hash->count);
+}
+
static void ftrace_hash_clear(struct ftrace_hash *hash)
{
struct hlist_head *hhd;
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 03/29] ftrace: Add add_ftrace_hash_entry function
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 01/29] ftrace: Add ftrace_hash_count function Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 02/29] ftrace: Add ftrace_hash_remove function Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 04/29] bpf: Use mutex lock pool for bpf trampolines Jiri Olsa
` (25 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Renaming __add_hash_entry to add_ftrace_hash_entry and making it global,
it will be used in following changes outside ftrace.c object.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/ftrace.h | 1 +
kernel/trace/ftrace.c | 9 ++++-----
2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/include/linux/ftrace.h b/include/linux/ftrace.h
index d3acfac4f8a7..cccbe21493ce 100644
--- a/include/linux/ftrace.h
+++ b/include/linux/ftrace.h
@@ -415,6 +415,7 @@ struct ftrace_hash *alloc_ftrace_hash(int size_bits);
void free_ftrace_hash(struct ftrace_hash *hash);
struct ftrace_func_entry *add_ftrace_hash_entry_direct(struct ftrace_hash *hash,
unsigned long ip, unsigned long direct);
+void add_ftrace_hash_entry(struct ftrace_hash *hash, struct ftrace_func_entry *entry);
void ftrace_hash_remove(struct ftrace_hash *hash);
/* The hash used to know what functions callbacks trace */
diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 45548b0200eb..f93e34dd2328 100644
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -1198,8 +1198,7 @@ ftrace_lookup_ip(struct ftrace_hash *hash, unsigned long ip)
return __ftrace_lookup_ip(hash, ip);
}
-static void __add_hash_entry(struct ftrace_hash *hash,
- struct ftrace_func_entry *entry)
+void add_ftrace_hash_entry(struct ftrace_hash *hash, struct ftrace_func_entry *entry)
{
struct hlist_head *hhd;
unsigned long key;
@@ -1221,7 +1220,7 @@ add_ftrace_hash_entry_direct(struct ftrace_hash *hash, unsigned long ip, unsigne
entry->ip = ip;
entry->direct = direct;
- __add_hash_entry(hash, entry);
+ add_ftrace_hash_entry(hash, entry);
return entry;
}
@@ -1477,7 +1476,7 @@ static struct ftrace_hash *__move_hash(struct ftrace_hash *src, int size)
hhd = &src->buckets[i];
hlist_for_each_entry_safe(entry, tn, hhd, hlist) {
remove_hash_entry(src, entry);
- __add_hash_entry(new_hash, entry);
+ add_ftrace_hash_entry(new_hash, entry);
}
}
return new_hash;
@@ -5360,7 +5359,7 @@ int ftrace_func_mapper_add_ip(struct ftrace_func_mapper *mapper,
map->entry.ip = ip;
map->data = data;
- __add_hash_entry(&mapper->hash, &map->entry);
+ add_ftrace_hash_entry(&mapper->hash, &map->entry);
return 0;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 04/29] bpf: Use mutex lock pool for bpf trampolines
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (2 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 03/29] ftrace: Add add_ftrace_hash_entry function Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 12:59 ` bot+bpf-ci
2026-05-27 11:39 ` [PATCHv6 bpf-next 05/29] bpf: Add struct bpf_trampoline_ops object Jiri Olsa
` (24 subsequent siblings)
28 siblings, 1 reply; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding mutex lock pool that replaces bpf trampolines mutex.
For tracing_multi link coming in following changes we need to lock all
the involved trampolines during the attachment. This could mean thousands
of mutex locks, which is not convenient.
As suggested by Andrii we can replace bpf trampolines mutex with mutex
pool, where each trampoline is hash-ed to one of the locks from the pool.
It's better to lock all the pool mutexes (32 at the moment) than
thousands of them.
There is 48 (MAX_LOCK_DEPTH) lock limit allowed to be simultaneously
held by task, so we need to keep 32 mutexes (5 bits) in the pool, so
when we lock them all in following changes the lockdep won't scream.
Removing the mutex_is_locked in bpf_trampoline_put, because we removed
the mutex from bpf_trampoline.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 2 --
kernel/bpf/trampoline.c | 77 ++++++++++++++++++++++++++++-------------
2 files changed, 53 insertions(+), 26 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 1c6863ce89e0..db89b3a591fa 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1351,8 +1351,6 @@ struct bpf_trampoline {
/* hlist for trampoline_ip_table */
struct hlist_node hlist_ip;
struct ftrace_ops *fops;
- /* serializes access to fields of this trampoline */
- struct mutex mutex;
refcount_t refcnt;
u32 flags;
u64 key;
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index a4298a25d4ba..df7634de0ca2 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -30,6 +30,35 @@ static struct hlist_head trampoline_ip_table[TRAMPOLINE_TABLE_SIZE];
/* serializes access to trampoline tables */
static DEFINE_MUTEX(trampoline_mutex);
+/*
+ * Keep 32 trampoline locks (5 bits) in the pool so trampoline_lock_all()
+ * stays below MAX_LOCK_DEPTH. Each pool slot has a distinct lockdep
+ * class because trampoline_lock_all() takes all pool mutexes at once;
+ * otherwise lockdep would report recursive locking on same-class mutexes.
+ */
+#define TRAMPOLINE_LOCKS_BITS 5
+#define TRAMPOLINE_LOCKS_TABLE_SIZE (1 << TRAMPOLINE_LOCKS_BITS)
+
+static struct {
+ struct mutex mutex;
+ struct lock_class_key key;
+} trampoline_locks[TRAMPOLINE_LOCKS_TABLE_SIZE];
+
+static struct mutex *select_trampoline_lock(struct bpf_trampoline *tr)
+{
+ return &trampoline_locks[hash_64((u64)(uintptr_t) tr, TRAMPOLINE_LOCKS_BITS)].mutex;
+}
+
+static void trampoline_lock(struct bpf_trampoline *tr)
+{
+ mutex_lock(select_trampoline_lock(tr));
+}
+
+static void trampoline_unlock(struct bpf_trampoline *tr)
+{
+ mutex_unlock(select_trampoline_lock(tr));
+}
+
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex);
@@ -69,9 +98,9 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
if (cmd == FTRACE_OPS_CMD_ENABLE_SHARE_IPMODIFY_SELF) {
/* This is called inside register_ftrace_direct_multi(), so
- * tr->mutex is already locked.
+ * trampoline's mutex is already locked.
*/
- lockdep_assert_held_once(&tr->mutex);
+ lockdep_assert_held_once(select_trampoline_lock(tr));
/* Instead of updating the trampoline here, we propagate
* -EAGAIN to register_ftrace_direct(). Then we can
@@ -91,7 +120,7 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
}
/* The normal locking order is
- * tr->mutex => direct_mutex (ftrace.c) => ftrace_lock (ftrace.c)
+ * select_trampoline_lock(tr) => direct_mutex (ftrace.c) => ftrace_lock (ftrace.c)
*
* The following two commands are called from
*
@@ -99,12 +128,12 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
* cleanup_direct_functions_after_ipmodify
*
* In both cases, direct_mutex is already locked. Use
- * mutex_trylock(&tr->mutex) to avoid deadlock in race condition
- * (something else is making changes to this same trampoline).
+ * mutex_trylock(select_trampoline_lock(tr)) to avoid deadlock in race condition
+ * (something else holds the same pool lock).
*/
- if (!mutex_trylock(&tr->mutex)) {
- /* sleep 1 ms to make sure whatever holding tr->mutex makes
- * some progress.
+ if (!mutex_trylock(select_trampoline_lock(tr))) {
+ /* sleep 1 ms to make sure whatever holding select_trampoline_lock(tr)
+ * makes some progress.
*/
msleep(1);
return -EAGAIN;
@@ -129,7 +158,7 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
break;
}
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
return ret;
}
#endif
@@ -359,7 +388,6 @@ static struct bpf_trampoline *bpf_trampoline_lookup(u64 key, unsigned long ip)
head = &trampoline_ip_table[hash_64(tr->ip, TRAMPOLINE_HASH_BITS)];
hlist_add_head(&tr->hlist_ip, head);
refcount_set(&tr->refcnt, 1);
- mutex_init(&tr->mutex);
for (i = 0; i < BPF_TRAMP_MAX; i++)
INIT_HLIST_HEAD(&tr->progs_hlist[i]);
out:
@@ -843,9 +871,9 @@ int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
{
int err;
- mutex_lock(&tr->mutex);
+ trampoline_lock(tr);
err = __bpf_trampoline_link_prog(link, tr, tgt_prog);
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
return err;
}
@@ -886,9 +914,9 @@ int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
{
int err;
- mutex_lock(&tr->mutex);
+ trampoline_lock(tr);
err = __bpf_trampoline_unlink_prog(link, tr, tgt_prog);
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
return err;
}
@@ -998,12 +1026,12 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
if (!tr)
return -ENOMEM;
- mutex_lock(&tr->mutex);
+ trampoline_lock(tr);
shim_link = cgroup_shim_find(tr, bpf_func);
if (shim_link && !IS_ERR(bpf_link_inc_not_zero(&shim_link->link.link))) {
/* Reusing existing shim attached by the other program. */
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
bpf_trampoline_put(tr); /* bpf_trampoline_get above */
return 0;
}
@@ -1023,16 +1051,16 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
shim_link->trampoline = tr;
/* note, we're still holding tr refcnt from above */
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
return 0;
err:
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
if (shim_link)
bpf_link_put(&shim_link->link.link);
- /* have to release tr while _not_ holding its mutex */
+ /* have to release tr while _not_ holding pool mutex for trampoline */
bpf_trampoline_put(tr); /* bpf_trampoline_get above */
return err;
@@ -1053,9 +1081,9 @@ void bpf_trampoline_unlink_cgroup_shim(struct bpf_prog *prog)
if (WARN_ON_ONCE(!tr))
return;
- mutex_lock(&tr->mutex);
+ trampoline_lock(tr);
shim_link = cgroup_shim_find(tr, bpf_func);
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
if (shim_link)
bpf_link_put(&shim_link->link.link);
@@ -1073,14 +1101,14 @@ struct bpf_trampoline *bpf_trampoline_get(u64 key,
if (!tr)
return NULL;
- mutex_lock(&tr->mutex);
+ trampoline_lock(tr);
if (tr->func.addr)
goto out;
memcpy(&tr->func.model, &tgt_info->fmodel, sizeof(tgt_info->fmodel));
tr->func.addr = (void *)tgt_info->tgt_addr;
out:
- mutex_unlock(&tr->mutex);
+ trampoline_unlock(tr);
return tr;
}
@@ -1093,7 +1121,6 @@ void bpf_trampoline_put(struct bpf_trampoline *tr)
mutex_lock(&trampoline_mutex);
if (!refcount_dec_and_test(&tr->refcnt))
goto out;
- WARN_ON_ONCE(mutex_is_locked(&tr->mutex));
for (i = 0; i < BPF_TRAMP_MAX; i++)
if (WARN_ON_ONCE(!hlist_empty(&tr->progs_hlist[i])))
@@ -1379,6 +1406,8 @@ static int __init init_trampolines(void)
INIT_HLIST_HEAD(&trampoline_key_table[i]);
for (i = 0; i < TRAMPOLINE_TABLE_SIZE; i++)
INIT_HLIST_HEAD(&trampoline_ip_table[i]);
+ for (i = 0; i < TRAMPOLINE_LOCKS_TABLE_SIZE; i++)
+ __mutex_init(&trampoline_locks[i].mutex, "trampoline_lock", &trampoline_locks[i].key);
return 0;
}
late_initcall(init_trampolines);
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* Re: [PATCHv6 bpf-next 04/29] bpf: Use mutex lock pool for bpf trampolines
2026-05-27 11:39 ` [PATCHv6 bpf-next 04/29] bpf: Use mutex lock pool for bpf trampolines Jiri Olsa
@ 2026-05-27 12:59 ` bot+bpf-ci
0 siblings, 0 replies; 34+ messages in thread
From: bot+bpf-ci @ 2026-05-27 12:59 UTC (permalink / raw)
To: jolsa, ast, daniel, andrii
Cc: bpf, linux-trace-kernel, kafai, eddyz87, songliubraving, yhs,
menglong8.dong, rostedt, ast, andrii, daniel, martin.lau, eddyz87,
yonghong.song, clm, ihor.solodrai
[-- Attachment #1: Type: text/plain, Size: 3093 bytes --]
> diff --git a/include/linux/bpf.h b/include/linux/bpf.h
> index 1c6863ce89e0..db89b3a591fa 100644
> --- a/include/linux/bpf.h
> +++ b/include/linux/bpf.h
[ ... ]
> diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
> index a4298a25d4ba..df7634de0ca2 100644
> --- a/kernel/bpf/trampoline.c
> +++ b/kernel/bpf/trampoline.c
> @@ -30,6 +30,35 @@ static struct hlist_head trampoline_ip_table[TRAMPOLINE_TABLE_SIZE];
> /* serializes access to trampoline tables */
> static DEFINE_MUTEX(trampoline_mutex);
>
> +/*
> + * Keep 32 trampoline locks (5 bits) in the pool so trampoline_lock_all()
> + * stays below MAX_LOCK_DEPTH. Each pool slot has a distinct lockdep
> + * class because trampoline_lock_all() takes all pool mutexes at once;
> + * otherwise lockdep would report recursive locking on same-class mutexes.
> + */
> +#define TRAMPOLINE_LOCKS_BITS 5
> +#define TRAMPOLINE_LOCKS_TABLE_SIZE (1 << TRAMPOLINE_LOCKS_BITS)
> +
> +static struct {
> + struct mutex mutex;
> + struct lock_class_key key;
> +} trampoline_locks[TRAMPOLINE_LOCKS_TABLE_SIZE];
> +
> +static struct mutex *select_trampoline_lock(struct bpf_trampoline *tr)
> +{
> + return &trampoline_locks[hash_64((u64)(uintptr_t) tr, TRAMPOLINE_LOCKS_BITS)].mutex;
> +}
[ ... ]
> @@ -99,12 +128,12 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
> * cleanup_direct_functions_after_ipmodify
> *
> * In both cases, direct_mutex is already locked. Use
> - * mutex_trylock(&tr->mutex) to avoid deadlock in race condition
> - * (something else is making changes to this same trampoline).
> + * mutex_trylock(select_trampoline_lock(tr)) to avoid deadlock in race condition
> + * (something else holds the same pool lock).
> */
> - if (!mutex_trylock(&tr->mutex)) {
> - /* sleep 1 ms to make sure whatever holding tr->mutex makes
> - * some progress.
> + if (!mutex_trylock(select_trampoline_lock(tr))) {
> + /* sleep 1 ms to make sure whatever holding select_trampoline_lock(tr)
> + * makes some progress.
> */
> msleep(1);
> return -EAGAIN;
With 32 trampolines sharing pool locks, can mutex_trylock fail spuriously
when an unrelated trampoline holds the same bucket?
If the trylock fails, the function returns -EAGAIN. Could this mean
concurrent ftrace or kprobe registrations might randomly fail due to false
sharing in the pool?
Also, when the upcoming tracing_multi feature locks all 32 mutexes at once,
wouldn't that deterministically abort any concurrent ftrace IPMODIFY
registrations system-wide?
Finally, if this trylock failure happens during unregistration, could
ftrace cleanup routines ignore the -EAGAIN, potentially leaving the
BPF_TRAMP_F_SHARE_IPMODIFY flag permanently set and corrupting the
trampoline state?
Reference: https://lore.kernel.org/bpf/20260418035227.168AEC19424@smtp.kernel.org/
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26509800686
^ permalink raw reply [flat|nested] 34+ messages in thread
* [PATCHv6 bpf-next 05/29] bpf: Add struct bpf_trampoline_ops object
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (3 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 04/29] bpf: Use mutex lock pool for bpf trampolines Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 06/29] bpf: Move trampoline image setup into bpf_trampoline_ops callbacks Jiri Olsa
` (23 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
In following changes we will need to override ftrace direct attachment
behaviour. In order to do that we are adding struct bpf_trampoline_ops
object that defines callbacks for ftrace direct attachment:
register_fentry
unregister_fentry
modify_fentry
The new struct bpf_trampoline_ops object is passed as an argument to
__bpf_trampoline_link/unlink_prog functions.
At the moment the default trampoline_ops is set to the current ftrace
direct attachment functions, so there's no functional change for the
current code.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/bpf/trampoline.c | 59 ++++++++++++++++++++++++++++-------------
1 file changed, 41 insertions(+), 18 deletions(-)
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index df7634de0ca2..848f256e1701 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -59,8 +59,18 @@ static void trampoline_unlock(struct bpf_trampoline *tr)
mutex_unlock(select_trampoline_lock(tr));
}
+struct bpf_trampoline_ops {
+ int (*register_fentry)(struct bpf_trampoline *tr, void *new_addr, void *data);
+ int (*unregister_fentry)(struct bpf_trampoline *tr, u32 orig_flags, void *old_addr,
+ void *data);
+ int (*modify_fentry)(struct bpf_trampoline *tr, u32 orig_flags, void *old_addr,
+ void *new_addr, bool lock_direct_mutex, void *data);
+};
+
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
-static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex);
+static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex,
+ const struct bpf_trampoline_ops *ops, void *data);
+static const struct bpf_trampoline_ops trampoline_ops;
#ifdef CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS
static struct bpf_trampoline *direct_ops_ip_lookup(struct ftrace_ops *ops, unsigned long ip)
@@ -145,13 +155,15 @@ static int bpf_tramp_ftrace_ops_func(struct ftrace_ops *ops, unsigned long ip,
if ((tr->flags & BPF_TRAMP_F_CALL_ORIG) &&
!(tr->flags & BPF_TRAMP_F_ORIG_STACK))
- ret = bpf_trampoline_update(tr, false /* lock_direct_mutex */);
+ ret = bpf_trampoline_update(tr, false /* lock_direct_mutex */,
+ &trampoline_ops, NULL);
break;
case FTRACE_OPS_CMD_DISABLE_SHARE_IPMODIFY_PEER:
tr->flags &= ~BPF_TRAMP_F_SHARE_IPMODIFY;
if (tr->flags & BPF_TRAMP_F_ORIG_STACK)
- ret = bpf_trampoline_update(tr, false /* lock_direct_mutex */);
+ ret = bpf_trampoline_update(tr, false /* lock_direct_mutex */,
+ &trampoline_ops, NULL);
break;
default:
ret = -EINVAL;
@@ -415,7 +427,7 @@ static int bpf_trampoline_update_fentry(struct bpf_trampoline *tr, u32 orig_flag
}
static int unregister_fentry(struct bpf_trampoline *tr, u32 orig_flags,
- void *old_addr)
+ void *old_addr, void *data __maybe_unused)
{
int ret;
@@ -429,7 +441,7 @@ static int unregister_fentry(struct bpf_trampoline *tr, u32 orig_flags,
static int modify_fentry(struct bpf_trampoline *tr, u32 orig_flags,
void *old_addr, void *new_addr,
- bool lock_direct_mutex)
+ bool lock_direct_mutex, void *data __maybe_unused)
{
int ret;
@@ -443,7 +455,7 @@ static int modify_fentry(struct bpf_trampoline *tr, u32 orig_flags,
}
/* first time registering */
-static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
+static int register_fentry(struct bpf_trampoline *tr, void *new_addr, void *data __maybe_unused)
{
void *ip = tr->func.addr;
unsigned long faddr;
@@ -465,6 +477,12 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr)
return ret;
}
+static const struct bpf_trampoline_ops trampoline_ops = {
+ .register_fentry = register_fentry,
+ .unregister_fentry = unregister_fentry,
+ .modify_fentry = modify_fentry,
+};
+
static struct bpf_tramp_links *
bpf_trampoline_get_progs(const struct bpf_trampoline *tr, int *total, bool *ip_arg)
{
@@ -632,7 +650,8 @@ static struct bpf_tramp_image *bpf_tramp_image_alloc(u64 key, int size)
return ERR_PTR(err);
}
-static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex)
+static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mutex,
+ const struct bpf_trampoline_ops *ops, void *data)
{
struct bpf_tramp_image *im;
struct bpf_tramp_links *tlinks;
@@ -645,7 +664,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
return PTR_ERR(tlinks);
if (total == 0) {
- err = unregister_fentry(tr, orig_flags, tr->cur_image->image);
+ err = ops->unregister_fentry(tr, orig_flags, tr->cur_image->image, data);
bpf_tramp_image_put(tr->cur_image);
tr->cur_image = NULL;
goto out;
@@ -715,11 +734,11 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
if (tr->cur_image)
/* progs already running at this address */
- err = modify_fentry(tr, orig_flags, tr->cur_image->image,
- im->image, lock_direct_mutex);
+ err = ops->modify_fentry(tr, orig_flags, tr->cur_image->image,
+ im->image, lock_direct_mutex, data);
else
/* first time registering */
- err = register_fentry(tr, im->image);
+ err = ops->register_fentry(tr, im->image, data);
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
if (err == -EAGAIN) {
@@ -793,7 +812,9 @@ static int bpf_freplace_check_tgt_prog(struct bpf_prog *tgt_prog)
static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
struct bpf_trampoline *tr,
- struct bpf_prog *tgt_prog)
+ struct bpf_prog *tgt_prog,
+ const struct bpf_trampoline_ops *ops,
+ void *data)
{
struct bpf_fsession_link *fslink = NULL;
enum bpf_tramp_prog_type kind;
@@ -851,7 +872,7 @@ static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
} else {
tr->progs_cnt[kind]++;
}
- err = bpf_trampoline_update(tr, true /* lock_direct_mutex */);
+ err = bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
if (err) {
hlist_del_init(&link->tramp_hlist);
if (kind == BPF_TRAMP_FSESSION) {
@@ -872,14 +893,16 @@ int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
int err;
trampoline_lock(tr);
- err = __bpf_trampoline_link_prog(link, tr, tgt_prog);
+ err = __bpf_trampoline_link_prog(link, tr, tgt_prog, &trampoline_ops, NULL);
trampoline_unlock(tr);
return err;
}
static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
struct bpf_trampoline *tr,
- struct bpf_prog *tgt_prog)
+ struct bpf_prog *tgt_prog,
+ const struct bpf_trampoline_ops *ops,
+ void *data)
{
enum bpf_tramp_prog_type kind;
int err;
@@ -904,7 +927,7 @@ static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
}
hlist_del_init(&link->tramp_hlist);
tr->progs_cnt[kind]--;
- return bpf_trampoline_update(tr, true /* lock_direct_mutex */);
+ return bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
}
/* bpf_trampoline_unlink_prog() should never fail. */
@@ -915,7 +938,7 @@ int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
int err;
trampoline_lock(tr);
- err = __bpf_trampoline_unlink_prog(link, tr, tgt_prog);
+ err = __bpf_trampoline_unlink_prog(link, tr, tgt_prog, &trampoline_ops, NULL);
trampoline_unlock(tr);
return err;
}
@@ -1044,7 +1067,7 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
goto err;
}
- err = __bpf_trampoline_link_prog(&shim_link->link, tr, NULL);
+ err = __bpf_trampoline_link_prog(&shim_link->link, tr, NULL, &trampoline_ops, NULL);
if (err)
goto err;
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 06/29] bpf: Move trampoline image setup into bpf_trampoline_ops callbacks
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (4 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 05/29] bpf: Add struct bpf_trampoline_ops object Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 07/29] bpf: Add bpf_trampoline_add/remove_prog functions Jiri Olsa
` (22 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Moving trampoline image setup into bpf_trampoline_ops callbacks,
so we can have different image handling for multi attachment which
is coming in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/bpf/trampoline.c | 66 ++++++++++++++++++++++++-----------------
1 file changed, 38 insertions(+), 28 deletions(-)
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 848f256e1701..7661738c1bd0 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -60,11 +60,10 @@ static void trampoline_unlock(struct bpf_trampoline *tr)
}
struct bpf_trampoline_ops {
- int (*register_fentry)(struct bpf_trampoline *tr, void *new_addr, void *data);
- int (*unregister_fentry)(struct bpf_trampoline *tr, u32 orig_flags, void *old_addr,
- void *data);
- int (*modify_fentry)(struct bpf_trampoline *tr, u32 orig_flags, void *old_addr,
- void *new_addr, bool lock_direct_mutex, void *data);
+ int (*register_fentry)(struct bpf_trampoline *tr, struct bpf_tramp_image *im, void *data);
+ int (*unregister_fentry)(struct bpf_trampoline *tr, u32 orig_flags, void *data);
+ int (*modify_fentry)(struct bpf_trampoline *tr, u32 orig_flags, struct bpf_tramp_image *im,
+ bool lock_direct_mutex, void *data);
};
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
@@ -426,9 +425,11 @@ static int bpf_trampoline_update_fentry(struct bpf_trampoline *tr, u32 orig_flag
return bpf_arch_text_poke(ip, old_t, new_t, old_addr, new_addr);
}
-static int unregister_fentry(struct bpf_trampoline *tr, u32 orig_flags,
- void *old_addr, void *data __maybe_unused)
+static void bpf_tramp_image_put(struct bpf_tramp_image *im);
+
+static int unregister_fentry(struct bpf_trampoline *tr, u32 orig_flags, void *data __maybe_unused)
{
+ void *old_addr = tr->cur_image->image;
int ret;
if (tr->func.ftrace_managed)
@@ -436,13 +437,19 @@ static int unregister_fentry(struct bpf_trampoline *tr, u32 orig_flags,
else
ret = bpf_trampoline_update_fentry(tr, orig_flags, old_addr, NULL);
- return ret;
+ if (ret)
+ return ret;
+
+ bpf_tramp_image_put(tr->cur_image);
+ tr->cur_image = NULL;
+ return 0;
}
-static int modify_fentry(struct bpf_trampoline *tr, u32 orig_flags,
- void *old_addr, void *new_addr,
+static int modify_fentry(struct bpf_trampoline *tr, u32 orig_flags, struct bpf_tramp_image *im,
bool lock_direct_mutex, void *data __maybe_unused)
{
+ void *old_addr = tr->cur_image->image;
+ void *new_addr = im->image;
int ret;
if (tr->func.ftrace_managed) {
@@ -451,12 +458,20 @@ static int modify_fentry(struct bpf_trampoline *tr, u32 orig_flags,
ret = bpf_trampoline_update_fentry(tr, orig_flags, old_addr,
new_addr);
}
- return ret;
+
+ if (ret)
+ return ret;
+
+ bpf_tramp_image_put(tr->cur_image);
+ tr->cur_image = im;
+ return 0;
}
/* first time registering */
-static int register_fentry(struct bpf_trampoline *tr, void *new_addr, void *data __maybe_unused)
+static int register_fentry(struct bpf_trampoline *tr, struct bpf_tramp_image *im,
+ void *data __maybe_unused)
{
+ void *new_addr = im->image;
void *ip = tr->func.addr;
unsigned long faddr;
int ret;
@@ -474,7 +489,11 @@ static int register_fentry(struct bpf_trampoline *tr, void *new_addr, void *data
ret = bpf_trampoline_update_fentry(tr, 0, NULL, new_addr);
}
- return ret;
+ if (ret)
+ return ret;
+
+ tr->cur_image = im;
+ return 0;
}
static const struct bpf_trampoline_ops trampoline_ops = {
@@ -664,9 +683,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
return PTR_ERR(tlinks);
if (total == 0) {
- err = ops->unregister_fentry(tr, orig_flags, tr->cur_image->image, data);
- bpf_tramp_image_put(tr->cur_image);
- tr->cur_image = NULL;
+ err = ops->unregister_fentry(tr, orig_flags, data);
goto out;
}
@@ -734,11 +751,10 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
if (tr->cur_image)
/* progs already running at this address */
- err = ops->modify_fentry(tr, orig_flags, tr->cur_image->image,
- im->image, lock_direct_mutex, data);
+ err = ops->modify_fentry(tr, orig_flags, im, lock_direct_mutex, data);
else
/* first time registering */
- err = ops->register_fentry(tr, im->image, data);
+ err = ops->register_fentry(tr, im, data);
#ifdef CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
if (err == -EAGAIN) {
@@ -750,22 +766,16 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
goto again;
}
#endif
- if (err)
- goto out_free;
- if (tr->cur_image)
- bpf_tramp_image_put(tr->cur_image);
- tr->cur_image = im;
+out_free:
+ if (err)
+ bpf_tramp_image_free(im);
out:
/* If any error happens, restore previous flags */
if (err)
tr->flags = orig_flags;
kfree(tlinks);
return err;
-
-out_free:
- bpf_tramp_image_free(im);
- goto out;
}
static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog)
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 07/29] bpf: Add bpf_trampoline_add/remove_prog functions
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (5 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 06/29] bpf: Move trampoline image setup into bpf_trampoline_ops callbacks Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 08/29] bpf: Add struct bpf_tramp_node object Jiri Olsa
` (21 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Separate bpf_trampoline_add/remove_prog functions from
__bpf_trampoline_link/unlink functions to be able to add/remove
trampoline programs without the image being updated in following
changes. No functional change is intended.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/bpf/trampoline.c | 108 +++++++++++++++++++++++-----------------
1 file changed, 61 insertions(+), 47 deletions(-)
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 7661738c1bd0..70724b0d8fb8 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -820,41 +820,16 @@ static int bpf_freplace_check_tgt_prog(struct bpf_prog *tgt_prog)
return 0;
}
-static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
- struct bpf_trampoline *tr,
- struct bpf_prog *tgt_prog,
- const struct bpf_trampoline_ops *ops,
- void *data)
+static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
+ struct bpf_tramp_link *link,
+ int cnt)
{
struct bpf_fsession_link *fslink = NULL;
enum bpf_tramp_prog_type kind;
struct bpf_tramp_link *link_exiting;
struct hlist_head *prog_list;
- int err = 0;
- int cnt = 0, i;
kind = bpf_attach_type_to_tramp(link->link.prog);
- if (tr->extension_prog)
- /* cannot attach fentry/fexit if extension prog is attached.
- * cannot overwrite extension prog either.
- */
- return -EBUSY;
-
- for (i = 0; i < BPF_TRAMP_MAX; i++)
- cnt += tr->progs_cnt[i];
-
- if (kind == BPF_TRAMP_REPLACE) {
- /* Cannot attach extension if fentry/fexit are in use. */
- if (cnt)
- return -EBUSY;
- err = bpf_freplace_check_tgt_prog(tgt_prog);
- if (err)
- return err;
- tr->extension_prog = link->link.prog;
- return bpf_arch_text_poke(tr->func.addr, BPF_MOD_NOP,
- BPF_MOD_JUMP, NULL,
- link->link.prog->bpf_func);
- }
if (kind == BPF_TRAMP_FSESSION) {
prog_list = &tr->progs_hlist[BPF_TRAMP_FENTRY];
cnt++;
@@ -882,17 +857,64 @@ static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
} else {
tr->progs_cnt[kind]++;
}
- err = bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
- if (err) {
- hlist_del_init(&link->tramp_hlist);
- if (kind == BPF_TRAMP_FSESSION) {
- tr->progs_cnt[BPF_TRAMP_FENTRY]--;
- hlist_del_init(&fslink->fexit.tramp_hlist);
- tr->progs_cnt[BPF_TRAMP_FEXIT]--;
- } else {
- tr->progs_cnt[kind]--;
- }
+ return 0;
+}
+
+static void bpf_trampoline_remove_prog(struct bpf_trampoline *tr,
+ struct bpf_tramp_link *link)
+{
+ struct bpf_fsession_link *fslink;
+ enum bpf_tramp_prog_type kind;
+
+ kind = bpf_attach_type_to_tramp(link->link.prog);
+ if (kind == BPF_TRAMP_FSESSION) {
+ fslink = container_of(link, struct bpf_fsession_link, link.link);
+ hlist_del_init(&fslink->fexit.tramp_hlist);
+ tr->progs_cnt[BPF_TRAMP_FEXIT]--;
+ kind = BPF_TRAMP_FENTRY;
+ }
+ hlist_del_init(&link->tramp_hlist);
+ tr->progs_cnt[kind]--;
+}
+
+static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
+ struct bpf_trampoline *tr,
+ struct bpf_prog *tgt_prog,
+ const struct bpf_trampoline_ops *ops,
+ void *data)
+{
+ enum bpf_tramp_prog_type kind;
+ int err = 0;
+ int cnt = 0, i;
+
+ kind = bpf_attach_type_to_tramp(link->link.prog);
+ if (tr->extension_prog)
+ /* cannot attach fentry/fexit if extension prog is attached.
+ * cannot overwrite extension prog either.
+ */
+ return -EBUSY;
+
+ for (i = 0; i < BPF_TRAMP_MAX; i++)
+ cnt += tr->progs_cnt[i];
+
+ if (kind == BPF_TRAMP_REPLACE) {
+ /* Cannot attach extension if fentry/fexit are in use. */
+ if (cnt)
+ return -EBUSY;
+ err = bpf_freplace_check_tgt_prog(tgt_prog);
+ if (err)
+ return err;
+ tr->extension_prog = link->link.prog;
+ return bpf_arch_text_poke(tr->func.addr, BPF_MOD_NOP,
+ BPF_MOD_JUMP, NULL,
+ link->link.prog->bpf_func);
}
+ err = bpf_trampoline_add_prog(tr, link, cnt);
+ if (err)
+ return err;
+ err = bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
+ if (err)
+ bpf_trampoline_remove_prog(tr, link);
return err;
}
@@ -927,16 +949,8 @@ static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
guard(mutex)(&tgt_prog->aux->ext_mutex);
tgt_prog->aux->is_extended = false;
return err;
- } else if (kind == BPF_TRAMP_FSESSION) {
- struct bpf_fsession_link *fslink =
- container_of(link, struct bpf_fsession_link, link.link);
-
- hlist_del_init(&fslink->fexit.tramp_hlist);
- tr->progs_cnt[BPF_TRAMP_FEXIT]--;
- kind = BPF_TRAMP_FENTRY;
}
- hlist_del_init(&link->tramp_hlist);
- tr->progs_cnt[kind]--;
+ bpf_trampoline_remove_prog(tr, link);
return bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 08/29] bpf: Add struct bpf_tramp_node object
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (6 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 07/29] bpf: Add bpf_trampoline_add/remove_prog functions Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 09/29] bpf: Factor fsession link to use struct bpf_tramp_node Jiri Olsa
` (20 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: Hengqi Chen, bpf, linux-trace-kernel, Martin KaFai Lau,
Eduard Zingerman, Song Liu, Yonghong Song, Menglong Dong,
Steven Rostedt
Adding struct bpf_tramp_node to decouple the link out of the trampoline
attachment info.
At the moment the object for attaching bpf program to the trampoline is
'struct bpf_tramp_link':
struct bpf_tramp_link {
struct bpf_link link;
struct hlist_node tramp_hlist;
u64 cookie;
}
The link holds the bpf_prog pointer and forces one link - one program
binding logic. In following changes we want to attach program to multiple
trampolines but we want to keep just one bpf_link object.
Splitting struct bpf_tramp_link into:
struct bpf_tramp_link {
struct bpf_link link;
struct bpf_tramp_node node;
};
struct bpf_tramp_node {
struct bpf_link *link;
struct hlist_node tramp_hlist;
u64 cookie;
};
The 'struct bpf_tramp_link' defines standard single trampoline link
and 'struct bpf_tramp_node' is the attachment trampoline object with
pointer to the bpf_link object.
This will allow us to define link for multiple trampolines, like:
struct bpf_tracing_multi_link {
struct bpf_link link;
...
int nodes_cnt;
struct bpf_tracing_multi_node nodes[] __counted_by(nodes_cnt);
};
Cc: Hengqi Chen <hengqi.chen@gmail.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
arch/arm64/net/bpf_jit_comp.c | 58 ++++++++--------
arch/loongarch/net/bpf_jit.c | 52 +++++++--------
arch/powerpc/net/bpf_jit_comp.c | 54 +++++++--------
arch/riscv/net/bpf_jit_comp64.c | 52 +++++++--------
arch/s390/net/bpf_jit_comp.c | 44 ++++++------
arch/x86/net/bpf_jit_comp.c | 54 +++++++--------
include/linux/bpf.h | 60 ++++++++++-------
kernel/bpf/bpf_struct_ops.c | 27 ++++----
kernel/bpf/syscall.c | 39 ++++++-----
kernel/bpf/trampoline.c | 115 ++++++++++++++++----------------
net/bpf/bpf_dummy_struct_ops.c | 14 ++--
11 files changed, 294 insertions(+), 275 deletions(-)
diff --git a/arch/arm64/net/bpf_jit_comp.c b/arch/arm64/net/bpf_jit_comp.c
index e3bbeaa94590..365c32a8e586 100644
--- a/arch/arm64/net/bpf_jit_comp.c
+++ b/arch/arm64/net/bpf_jit_comp.c
@@ -2333,24 +2333,24 @@ bool bpf_jit_supports_subprog_tailcalls(void)
return true;
}
-static void invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_link *l,
+static void invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_node *node,
int bargs_off, int retval_off, int run_ctx_off,
bool save_ret)
{
__le32 *branch;
u64 enter_prog;
u64 exit_prog;
- struct bpf_prog *p = l->link.prog;
+ struct bpf_prog *p = node->link->prog;
int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
enter_prog = (u64)bpf_trampoline_enter(p);
exit_prog = (u64)bpf_trampoline_exit(p);
- if (l->cookie == 0) {
+ if (node->cookie == 0) {
/* if cookie is zero, one instruction is enough to store it */
emit(A64_STR64I(A64_ZR, A64_SP, run_ctx_off + cookie_off), ctx);
} else {
- emit_a64_mov_i64(A64_R(10), l->cookie, ctx);
+ emit_a64_mov_i64(A64_R(10), node->cookie, ctx);
emit(A64_STR64I(A64_R(10), A64_SP, run_ctx_off + cookie_off),
ctx);
}
@@ -2400,7 +2400,7 @@ static void invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_link *l,
emit_call(exit_prog, ctx);
}
-static void invoke_bpf_mod_ret(struct jit_ctx *ctx, struct bpf_tramp_links *tl,
+static void invoke_bpf_mod_ret(struct jit_ctx *ctx, struct bpf_tramp_nodes *tn,
int bargs_off, int retval_off, int run_ctx_off,
__le32 **branches)
{
@@ -2410,8 +2410,8 @@ static void invoke_bpf_mod_ret(struct jit_ctx *ctx, struct bpf_tramp_links *tl,
* Set this to 0 to avoid confusing the program.
*/
emit(A64_STR64I(A64_ZR, A64_SP, retval_off), ctx);
- for (i = 0; i < tl->nr_links; i++) {
- invoke_bpf_prog(ctx, tl->links[i], bargs_off, retval_off,
+ for (i = 0; i < tn->nr_nodes; i++) {
+ invoke_bpf_prog(ctx, tn->nodes[i], bargs_off, retval_off,
run_ctx_off, true);
/* if (*(u64 *)(sp + retval_off) != 0)
* goto do_fexit;
@@ -2542,10 +2542,10 @@ static void restore_args(struct jit_ctx *ctx, int bargs_off, int nregs)
}
}
-static bool is_struct_ops_tramp(const struct bpf_tramp_links *fentry_links)
+static bool is_struct_ops_tramp(const struct bpf_tramp_nodes *fentry_nodes)
{
- return fentry_links->nr_links == 1 &&
- fentry_links->links[0]->link.type == BPF_LINK_TYPE_STRUCT_OPS;
+ return fentry_nodes->nr_nodes == 1 &&
+ fentry_nodes->nodes[0]->link->type == BPF_LINK_TYPE_STRUCT_OPS;
}
static void store_func_meta(struct jit_ctx *ctx, u64 func_meta, int func_meta_off)
@@ -2566,7 +2566,7 @@ static void store_func_meta(struct jit_ctx *ctx, u64 func_meta, int func_meta_of
*
*/
static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
- struct bpf_tramp_links *tlinks, void *func_addr,
+ struct bpf_tramp_nodes *tnodes, void *func_addr,
const struct btf_func_model *m,
const struct arg_aux *a,
u32 flags)
@@ -2582,14 +2582,14 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
int run_ctx_off;
int oargs_off;
int nfuncargs;
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
bool save_ret;
__le32 **branches = NULL;
bool is_struct_ops = is_struct_ops_tramp(fentry);
int cookie_off, cookie_cnt, cookie_bargs_off;
- int fsession_cnt = bpf_fsession_cnt(tlinks);
+ int fsession_cnt = bpf_fsession_cnt(tnodes);
u64 func_meta;
/* trampoline stack layout:
@@ -2635,7 +2635,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
cookie_off = stack_size;
/* room for session cookies */
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
stack_size += cookie_cnt * 8;
ip_off = stack_size;
@@ -2732,20 +2732,20 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
}
cookie_bargs_off = (bargs_off - cookie_off) / 8;
- for (i = 0; i < fentry->nr_links; i++) {
- if (bpf_prog_calls_session_cookie(fentry->links[i])) {
+ for (i = 0; i < fentry->nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(fentry->nodes[i])) {
u64 meta = func_meta | (cookie_bargs_off << BPF_TRAMP_COOKIE_INDEX_SHIFT);
store_func_meta(ctx, meta, func_meta_off);
cookie_bargs_off--;
}
- invoke_bpf_prog(ctx, fentry->links[i], bargs_off,
+ invoke_bpf_prog(ctx, fentry->nodes[i], bargs_off,
retval_off, run_ctx_off,
flags & BPF_TRAMP_F_RET_FENTRY_RET);
}
- if (fmod_ret->nr_links) {
- branches = kcalloc(fmod_ret->nr_links, sizeof(__le32 *),
+ if (fmod_ret->nr_nodes) {
+ branches = kcalloc(fmod_ret->nr_nodes, sizeof(__le32 *),
GFP_KERNEL);
if (!branches)
return -ENOMEM;
@@ -2769,7 +2769,7 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
}
/* update the branches saved in invoke_bpf_mod_ret with cbnz */
- for (i = 0; i < fmod_ret->nr_links && ctx->image != NULL; i++) {
+ for (i = 0; i < fmod_ret->nr_nodes && ctx->image != NULL; i++) {
int offset = &ctx->image[ctx->idx] - branches[i];
*branches[i] = cpu_to_le32(A64_CBNZ(1, A64_R(10), offset));
}
@@ -2780,14 +2780,14 @@ static int prepare_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
store_func_meta(ctx, func_meta, func_meta_off);
cookie_bargs_off = (bargs_off - cookie_off) / 8;
- for (i = 0; i < fexit->nr_links; i++) {
- if (bpf_prog_calls_session_cookie(fexit->links[i])) {
+ for (i = 0; i < fexit->nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(fexit->nodes[i])) {
u64 meta = func_meta | (cookie_bargs_off << BPF_TRAMP_COOKIE_INDEX_SHIFT);
store_func_meta(ctx, meta, func_meta_off);
cookie_bargs_off--;
}
- invoke_bpf_prog(ctx, fexit->links[i], bargs_off, retval_off,
+ invoke_bpf_prog(ctx, fexit->nodes[i], bargs_off, retval_off,
run_ctx_off, false);
}
@@ -2845,7 +2845,7 @@ bool bpf_jit_supports_fsession(void)
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
struct jit_ctx ctx = {
.image = NULL,
@@ -2859,7 +2859,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
if (ret < 0)
return ret;
- ret = prepare_trampoline(&ctx, &im, tlinks, func_addr, m, &aaux, flags);
+ ret = prepare_trampoline(&ctx, &im, tnodes, func_addr, m, &aaux, flags);
if (ret < 0)
return ret;
@@ -2883,7 +2883,7 @@ int arch_protect_bpf_trampoline(void *image, unsigned int size)
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
void *ro_image_end, const struct btf_func_model *m,
- u32 flags, struct bpf_tramp_links *tlinks,
+ u32 flags, struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
u32 size = ro_image_end - ro_image;
@@ -2910,7 +2910,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
ret = calc_arg_aux(m, &aaux);
if (ret)
goto out;
- ret = prepare_trampoline(&ctx, im, tlinks, func_addr, m, &aaux, flags);
+ ret = prepare_trampoline(&ctx, im, tnodes, func_addr, m, &aaux, flags);
if (ret > 0 && validate_code(&ctx) < 0) {
ret = -EINVAL;
diff --git a/arch/loongarch/net/bpf_jit.c b/arch/loongarch/net/bpf_jit.c
index 24913dc7f4e8..058ffbbaad85 100644
--- a/arch/loongarch/net/bpf_jit.c
+++ b/arch/loongarch/net/bpf_jit.c
@@ -1674,17 +1674,17 @@ static void restore_stk_args(struct jit_ctx *ctx, int nr_stk_args, int args_off,
}
}
-static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_link *l,
+static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_node *n,
int args_off, int retval_off, int run_ctx_off, bool save_ret)
{
int ret;
u32 *branch;
- struct bpf_prog *p = l->link.prog;
+ struct bpf_prog *p = n->link->prog;
int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
- if (l->cookie)
+ if (n->cookie)
emit_store_stack_imm64(ctx, LOONGARCH_GPR_T1,
- -run_ctx_off + cookie_off, l->cookie);
+ -run_ctx_off + cookie_off, n->cookie);
else
emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -run_ctx_off + cookie_off);
@@ -1737,22 +1737,22 @@ static int invoke_bpf_prog(struct jit_ctx *ctx, struct bpf_tramp_link *l,
return ret;
}
-static int invoke_bpf(struct jit_ctx *ctx, struct bpf_tramp_links *tl,
+static int invoke_bpf(struct jit_ctx *ctx, struct bpf_tramp_nodes *tn,
int args_off, int retval_off, int run_ctx_off,
int func_meta_off, bool save_ret, u64 func_meta, int cookie_off)
{
int i, cur_cookie = (cookie_off - args_off) / 8;
- for (i = 0; i < tl->nr_links; i++) {
+ for (i = 0; i < tn->nr_nodes; i++) {
int err;
- if (bpf_prog_calls_session_cookie(tl->links[i])) {
+ if (bpf_prog_calls_session_cookie(tn->nodes[i])) {
u64 meta = func_meta | ((u64)cur_cookie << BPF_TRAMP_COOKIE_INDEX_SHIFT);
emit_store_stack_imm64(ctx, LOONGARCH_GPR_T1, -func_meta_off, meta);
cur_cookie--;
}
- err = invoke_bpf_prog(ctx, tl->links[i], args_off, retval_off, run_ctx_off, save_ret);
+ err = invoke_bpf_prog(ctx, tn->nodes[i], args_off, retval_off, run_ctx_off, save_ret);
if (err)
return err;
}
@@ -1807,7 +1807,7 @@ static void sign_extend(struct jit_ctx *ctx, int rd, int rj, u8 size, bool sign)
}
static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_image *im,
- const struct btf_func_model *m, struct bpf_tramp_links *tlinks,
+ const struct btf_func_model *m, struct bpf_tramp_nodes *tnodes,
void *func_addr, u32 flags)
{
int i, ret, save_ret;
@@ -1817,9 +1817,9 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
unsigned long long func_meta;
bool is_struct_ops = flags & BPF_TRAMP_F_INDIRECT;
void *orig_call = func_addr;
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
u32 **branches = NULL;
/*
@@ -1898,7 +1898,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
ip_off = stack_size;
}
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
/* Room for session cookies */
stack_size += cookie_cnt * 8;
@@ -1969,7 +1969,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
store_args(ctx, nr_arg_slots, args_off);
- if (bpf_fsession_cnt(tlinks)) {
+ if (bpf_fsession_cnt(tnodes)) {
/* clear all session cookies' value */
for (i = 0; i < cookie_cnt; i++)
emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -cookie_off + 8 * i);
@@ -1994,20 +1994,20 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
return ret;
}
- if (fentry->nr_links) {
+ if (fentry->nr_nodes) {
ret = invoke_bpf(ctx, fentry, args_off, retval_off, run_ctx_off, func_meta_off,
flags & BPF_TRAMP_F_RET_FENTRY_RET, func_meta, cookie_off);
if (ret)
return ret;
}
- if (fmod_ret->nr_links) {
- branches = kcalloc(fmod_ret->nr_links, sizeof(u32 *), GFP_KERNEL);
+ if (fmod_ret->nr_nodes) {
+ branches = kcalloc(fmod_ret->nr_nodes, sizeof(u32 *), GFP_KERNEL);
if (!branches)
return -ENOMEM;
emit_insn(ctx, std, LOONGARCH_GPR_ZERO, LOONGARCH_GPR_FP, -retval_off);
- for (i = 0; i < fmod_ret->nr_links; i++) {
- ret = invoke_bpf_prog(ctx, fmod_ret->links[i],
+ for (i = 0; i < fmod_ret->nr_nodes; i++) {
+ ret = invoke_bpf_prog(ctx, fmod_ret->nodes[i],
args_off, retval_off, run_ctx_off, true);
if (ret)
goto out;
@@ -2035,17 +2035,17 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
emit_insn(ctx, nop);
}
- for (i = 0; ctx->image && i < fmod_ret->nr_links; i++) {
+ for (i = 0; ctx->image && i < fmod_ret->nr_nodes; i++) {
int offset = (void *)(&ctx->image[ctx->idx]) - (void *)branches[i];
*branches[i] = larch_insn_gen_bne(LOONGARCH_GPR_T1, LOONGARCH_GPR_ZERO, offset);
}
/* Set "is_return" flag for fsession */
func_meta |= (1ULL << BPF_TRAMP_IS_RETURN_SHIFT);
- if (bpf_fsession_cnt(tlinks))
+ if (bpf_fsession_cnt(tnodes))
emit_store_stack_imm64(ctx, LOONGARCH_GPR_T1, -func_meta_off, func_meta);
- if (fexit->nr_links) {
+ if (fexit->nr_nodes) {
ret = invoke_bpf(ctx, fexit, args_off, retval_off, run_ctx_off,
func_meta_off, false, func_meta, cookie_off);
if (ret)
@@ -2115,7 +2115,7 @@ static int __arch_prepare_bpf_trampoline(struct jit_ctx *ctx, struct bpf_tramp_i
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
void *ro_image_end, const struct btf_func_model *m,
- u32 flags, struct bpf_tramp_links *tlinks, void *func_addr)
+ u32 flags, struct bpf_tramp_nodes *tnodes, void *func_addr)
{
int ret, size;
void *image, *tmp;
@@ -2131,7 +2131,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
ctx.idx = 0;
jit_fill_hole(image, (unsigned int)(ro_image_end - ro_image));
- ret = __arch_prepare_bpf_trampoline(&ctx, im, m, tlinks, func_addr, flags);
+ ret = __arch_prepare_bpf_trampoline(&ctx, im, m, tnodes, func_addr, flags);
if (ret < 0)
goto out;
@@ -2152,7 +2152,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
int ret;
struct jit_ctx ctx;
@@ -2161,7 +2161,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
ctx.image = NULL;
ctx.idx = 0;
- ret = __arch_prepare_bpf_trampoline(&ctx, &im, m, tlinks, func_addr, flags);
+ ret = __arch_prepare_bpf_trampoline(&ctx, &im, m, tnodes, func_addr, flags);
return ret < 0 ? ret : ret * LOONGARCH_INSN_SIZE;
}
diff --git a/arch/powerpc/net/bpf_jit_comp.c b/arch/powerpc/net/bpf_jit_comp.c
index 53ab97ad6074..6351a187ca61 100644
--- a/arch/powerpc/net/bpf_jit_comp.c
+++ b/arch/powerpc/net/bpf_jit_comp.c
@@ -597,22 +597,22 @@ int arch_protect_bpf_trampoline(void *image, unsigned int size)
}
static int invoke_bpf_prog(u32 *image, u32 *ro_image, struct codegen_context *ctx,
- struct bpf_tramp_link *l, int regs_off, int retval_off,
+ struct bpf_tramp_node *n, int regs_off, int retval_off,
int run_ctx_off, bool save_ret)
{
- struct bpf_prog *p = l->link.prog;
+ struct bpf_prog *p = n->link->prog;
ppc_inst_t branch_insn;
u32 jmp_idx;
int ret = 0;
/* Save cookie */
if (IS_ENABLED(CONFIG_PPC64)) {
- PPC_LI64(_R3, l->cookie);
+ PPC_LI64(_R3, n->cookie);
EMIT(PPC_RAW_STD(_R3, _R1, run_ctx_off + offsetof(struct bpf_tramp_run_ctx,
bpf_cookie)));
} else {
- PPC_LI32(_R3, l->cookie >> 32);
- PPC_LI32(_R4, l->cookie);
+ PPC_LI32(_R3, n->cookie >> 32);
+ PPC_LI32(_R4, n->cookie);
EMIT(PPC_RAW_STW(_R3, _R1,
run_ctx_off + offsetof(struct bpf_tramp_run_ctx, bpf_cookie)));
EMIT(PPC_RAW_STW(_R4, _R1,
@@ -679,7 +679,7 @@ static int invoke_bpf_prog(u32 *image, u32 *ro_image, struct codegen_context *ct
}
static int invoke_bpf_mod_ret(u32 *image, u32 *ro_image, struct codegen_context *ctx,
- struct bpf_tramp_links *tl, int regs_off, int retval_off,
+ struct bpf_tramp_nodes *tn, int regs_off, int retval_off,
int run_ctx_off, u32 *branches)
{
int i;
@@ -690,8 +690,8 @@ static int invoke_bpf_mod_ret(u32 *image, u32 *ro_image, struct codegen_context
*/
EMIT(PPC_RAW_LI(_R3, 0));
EMIT(PPC_RAW_STL(_R3, _R1, retval_off));
- for (i = 0; i < tl->nr_links; i++) {
- if (invoke_bpf_prog(image, ro_image, ctx, tl->links[i], regs_off, retval_off,
+ for (i = 0; i < tn->nr_nodes; i++) {
+ if (invoke_bpf_prog(image, ro_image, ctx, tn->nodes[i], regs_off, retval_off,
run_ctx_off, true))
return -EINVAL;
@@ -807,18 +807,18 @@ static void bpf_trampoline_restore_args_stack(u32 *image, struct codegen_context
static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_image,
void *rw_image_end, void *ro_image,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
int regs_off, func_meta_off, ip_off, run_ctx_off, retval_off;
int nvr_off, alt_lr_off, r4_off = 0;
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
int i, ret, nr_regs, retaddr_off, bpf_frame_size = 0;
struct codegen_context codegen_ctx, *ctx;
int cookie_off, cookie_cnt, cookie_ctx_off;
- int fsession_cnt = bpf_fsession_cnt(tlinks);
+ int fsession_cnt = bpf_fsession_cnt(tnodes);
u64 func_meta;
u32 *image = (u32 *)rw_image;
ppc_inst_t branch_insn;
@@ -893,7 +893,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
/* room for session cookies */
cookie_off = bpf_frame_size;
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
bpf_frame_size += cookie_cnt * 8;
/* Room for IP address argument */
@@ -1030,21 +1030,21 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
cookie_ctx_off = (regs_off - cookie_off) / 8;
- for (i = 0; i < fentry->nr_links; i++) {
- if (bpf_prog_calls_session_cookie(fentry->links[i])) {
+ for (i = 0; i < fentry->nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(fentry->nodes[i])) {
u64 meta = func_meta | (cookie_ctx_off << BPF_TRAMP_COOKIE_INDEX_SHIFT);
store_func_meta(image, ctx, meta, func_meta_off);
cookie_ctx_off--;
}
- if (invoke_bpf_prog(image, ro_image, ctx, fentry->links[i], regs_off, retval_off,
+ if (invoke_bpf_prog(image, ro_image, ctx, fentry->nodes[i], regs_off, retval_off,
run_ctx_off, flags & BPF_TRAMP_F_RET_FENTRY_RET))
return -EINVAL;
}
- if (fmod_ret->nr_links) {
- branches = kcalloc(fmod_ret->nr_links, sizeof(u32), GFP_KERNEL);
+ if (fmod_ret->nr_nodes) {
+ branches = kcalloc(fmod_ret->nr_nodes, sizeof(u32), GFP_KERNEL);
if (!branches)
return -ENOMEM;
@@ -1093,7 +1093,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
}
/* Update branches saved in invoke_bpf_mod_ret with address of do_fexit */
- for (i = 0; i < fmod_ret->nr_links && image; i++) {
+ for (i = 0; i < fmod_ret->nr_nodes && image; i++) {
if (create_cond_branch(&branch_insn, &image[branches[i]],
(unsigned long)&image[ctx->idx], COND_NE << 16)) {
ret = -EINVAL;
@@ -1110,15 +1110,15 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
cookie_ctx_off = (regs_off - cookie_off) / 8;
- for (i = 0; i < fexit->nr_links; i++) {
- if (bpf_prog_calls_session_cookie(fexit->links[i])) {
+ for (i = 0; i < fexit->nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(fexit->nodes[i])) {
u64 meta = func_meta | (cookie_ctx_off << BPF_TRAMP_COOKIE_INDEX_SHIFT);
store_func_meta(image, ctx, meta, func_meta_off);
cookie_ctx_off--;
}
- if (invoke_bpf_prog(image, ro_image, ctx, fexit->links[i], regs_off, retval_off,
+ if (invoke_bpf_prog(image, ro_image, ctx, fexit->nodes[i], regs_off, retval_off,
run_ctx_off, false)) {
ret = -EINVAL;
goto cleanup;
@@ -1185,18 +1185,18 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
struct bpf_tramp_image im;
int ret;
- ret = __arch_prepare_bpf_trampoline(&im, NULL, NULL, NULL, m, flags, tlinks, func_addr);
+ ret = __arch_prepare_bpf_trampoline(&im, NULL, NULL, NULL, m, flags, tnodes, func_addr);
return ret;
}
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
u32 size = image_end - image;
@@ -1212,7 +1212,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
return -ENOMEM;
ret = __arch_prepare_bpf_trampoline(im, rw_image, rw_image + size, image, m,
- flags, tlinks, func_addr);
+ flags, tnodes, func_addr);
if (ret < 0)
goto out;
diff --git a/arch/riscv/net/bpf_jit_comp64.c b/arch/riscv/net/bpf_jit_comp64.c
index 2f1109dbf105..461b902a5f92 100644
--- a/arch/riscv/net/bpf_jit_comp64.c
+++ b/arch/riscv/net/bpf_jit_comp64.c
@@ -934,15 +934,15 @@ static void emit_store_stack_imm64(u8 reg, int stack_off, u64 imm64,
emit_sd(RV_REG_FP, stack_off, reg, ctx);
}
-static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_off,
+static int invoke_bpf_prog(struct bpf_tramp_node *node, int args_off, int retval_off,
int run_ctx_off, bool save_ret, struct rv_jit_context *ctx)
{
int ret, branch_off;
- struct bpf_prog *p = l->link.prog;
+ struct bpf_prog *p = node->link->prog;
int cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
- if (l->cookie)
- emit_store_stack_imm64(RV_REG_T1, -run_ctx_off + cookie_off, l->cookie, ctx);
+ if (node->cookie)
+ emit_store_stack_imm64(RV_REG_T1, -run_ctx_off + cookie_off, node->cookie, ctx);
else
emit_sd(RV_REG_FP, -run_ctx_off + cookie_off, RV_REG_ZERO, ctx);
@@ -996,22 +996,22 @@ static int invoke_bpf_prog(struct bpf_tramp_link *l, int args_off, int retval_of
return ret;
}
-static int invoke_bpf(struct bpf_tramp_links *tl, int args_off, int retval_off,
+static int invoke_bpf(struct bpf_tramp_nodes *tn, int args_off, int retval_off,
int run_ctx_off, int func_meta_off, bool save_ret, u64 func_meta,
int cookie_off, struct rv_jit_context *ctx)
{
int i, cur_cookie = (cookie_off - args_off) / 8;
- for (i = 0; i < tl->nr_links; i++) {
+ for (i = 0; i < tn->nr_nodes; i++) {
int err;
- if (bpf_prog_calls_session_cookie(tl->links[i])) {
+ if (bpf_prog_calls_session_cookie(tn->nodes[i])) {
u64 meta = func_meta | ((u64)cur_cookie << BPF_TRAMP_COOKIE_INDEX_SHIFT);
emit_store_stack_imm64(RV_REG_T1, -func_meta_off, meta, ctx);
cur_cookie--;
}
- err = invoke_bpf_prog(tl->links[i], args_off, retval_off, run_ctx_off,
+ err = invoke_bpf_prog(tn->nodes[i], args_off, retval_off, run_ctx_off,
save_ret, ctx);
if (err)
return err;
@@ -1021,7 +1021,7 @@ static int invoke_bpf(struct bpf_tramp_links *tl, int args_off, int retval_off,
static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
const struct btf_func_model *m,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr, u32 flags,
struct rv_jit_context *ctx)
{
@@ -1030,9 +1030,9 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
int stack_size = 0, nr_arg_slots = 0;
int retval_off, args_off, func_meta_off, ip_off, run_ctx_off, sreg_off, stk_arg_off;
int cookie_off, cookie_cnt;
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
bool is_struct_ops = flags & BPF_TRAMP_F_INDIRECT;
void *orig_call = func_addr;
bool save_ret;
@@ -1115,7 +1115,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
ip_off = stack_size;
}
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
/* room for session cookies */
stack_size += cookie_cnt * 8;
cookie_off = stack_size;
@@ -1172,7 +1172,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
store_args(nr_arg_slots, args_off, ctx);
- if (bpf_fsession_cnt(tlinks)) {
+ if (bpf_fsession_cnt(tnodes)) {
/* clear all session cookies' value */
for (i = 0; i < cookie_cnt; i++)
emit_sd(RV_REG_FP, -cookie_off + 8 * i, RV_REG_ZERO, ctx);
@@ -1187,22 +1187,22 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
return ret;
}
- if (fentry->nr_links) {
+ if (fentry->nr_nodes) {
ret = invoke_bpf(fentry, args_off, retval_off, run_ctx_off, func_meta_off,
flags & BPF_TRAMP_F_RET_FENTRY_RET, func_meta, cookie_off, ctx);
if (ret)
return ret;
}
- if (fmod_ret->nr_links) {
- branches_off = kzalloc_objs(int, fmod_ret->nr_links);
+ if (fmod_ret->nr_nodes) {
+ branches_off = kzalloc_objs(int, fmod_ret->nr_nodes);
if (!branches_off)
return -ENOMEM;
/* cleanup to avoid garbage return value confusion */
emit_sd(RV_REG_FP, -retval_off, RV_REG_ZERO, ctx);
- for (i = 0; i < fmod_ret->nr_links; i++) {
- ret = invoke_bpf_prog(fmod_ret->links[i], args_off, retval_off,
+ for (i = 0; i < fmod_ret->nr_nodes; i++) {
+ ret = invoke_bpf_prog(fmod_ret->nodes[i], args_off, retval_off,
run_ctx_off, true, ctx);
if (ret)
goto out;
@@ -1230,7 +1230,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
}
/* update branches saved in invoke_bpf_mod_ret with bnez */
- for (i = 0; ctx->insns && i < fmod_ret->nr_links; i++) {
+ for (i = 0; ctx->insns && i < fmod_ret->nr_nodes; i++) {
offset = ninsns_rvoff(ctx->ninsns - branches_off[i]);
insn = rv_bne(RV_REG_T1, RV_REG_ZERO, offset >> 1);
*(u32 *)(ctx->insns + branches_off[i]) = insn;
@@ -1238,10 +1238,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
/* set "is_return" flag for fsession */
func_meta |= (1ULL << BPF_TRAMP_IS_RETURN_SHIFT);
- if (bpf_fsession_cnt(tlinks))
+ if (bpf_fsession_cnt(tnodes))
emit_store_stack_imm64(RV_REG_T1, -func_meta_off, func_meta, ctx);
- if (fexit->nr_links) {
+ if (fexit->nr_nodes) {
ret = invoke_bpf(fexit, args_off, retval_off, run_ctx_off, func_meta_off,
false, func_meta, cookie_off, ctx);
if (ret)
@@ -1305,7 +1305,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
struct bpf_tramp_image im;
struct rv_jit_context ctx;
@@ -1314,7 +1314,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
ctx.ninsns = 0;
ctx.insns = NULL;
ctx.ro_insns = NULL;
- ret = __arch_prepare_bpf_trampoline(&im, m, tlinks, func_addr, flags, &ctx);
+ ret = __arch_prepare_bpf_trampoline(&im, m, tnodes, func_addr, flags, &ctx);
return ret < 0 ? ret : ninsns_rvoff(ctx.ninsns);
}
@@ -1331,7 +1331,7 @@ void arch_free_bpf_trampoline(void *image, unsigned int size)
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
void *ro_image_end, const struct btf_func_model *m,
- u32 flags, struct bpf_tramp_links *tlinks,
+ u32 flags, struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
int ret;
@@ -1346,7 +1346,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *ro_image,
ctx.ninsns = 0;
ctx.insns = image;
ctx.ro_insns = ro_image;
- ret = __arch_prepare_bpf_trampoline(im, m, tlinks, func_addr, flags, &ctx);
+ ret = __arch_prepare_bpf_trampoline(im, m, tnodes, func_addr, flags, &ctx);
if (ret < 0)
goto out;
diff --git a/arch/s390/net/bpf_jit_comp.c b/arch/s390/net/bpf_jit_comp.c
index 14eaaa5b2185..31749c0362ca 100644
--- a/arch/s390/net/bpf_jit_comp.c
+++ b/arch/s390/net/bpf_jit_comp.c
@@ -2537,19 +2537,19 @@ static void emit_store_stack_imm64(struct bpf_jit *jit, int tmp_reg, int stack_o
static int invoke_bpf_prog(struct bpf_tramp_jit *tjit,
const struct btf_func_model *m,
- struct bpf_tramp_link *tlink, bool save_ret)
+ struct bpf_tramp_node *node, bool save_ret)
{
struct bpf_jit *jit = &tjit->common;
int cookie_off = tjit->run_ctx_off +
offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
- struct bpf_prog *p = tlink->link.prog;
+ struct bpf_prog *p = node->link->prog;
int patch;
/*
- * run_ctx.cookie = tlink->cookie;
+ * run_ctx.cookie = node->cookie;
*/
- emit_store_stack_imm64(jit, REG_W0, cookie_off, tlink->cookie);
+ emit_store_stack_imm64(jit, REG_W0, cookie_off, node->cookie);
/*
* if ((start = __bpf_prog_enter(p, &run_ctx)) == 0)
@@ -2609,20 +2609,20 @@ static int invoke_bpf_prog(struct bpf_tramp_jit *tjit,
static int invoke_bpf(struct bpf_tramp_jit *tjit,
const struct btf_func_model *m,
- struct bpf_tramp_links *tl, bool save_ret,
+ struct bpf_tramp_nodes *tn, bool save_ret,
u64 func_meta, int cookie_off)
{
int i, cur_cookie = (tjit->bpf_args_off - cookie_off) / sizeof(u64);
struct bpf_jit *jit = &tjit->common;
- for (i = 0; i < tl->nr_links; i++) {
- if (bpf_prog_calls_session_cookie(tl->links[i])) {
+ for (i = 0; i < tn->nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(tn->nodes[i])) {
u64 meta = func_meta | ((u64)cur_cookie << BPF_TRAMP_COOKIE_INDEX_SHIFT);
emit_store_stack_imm64(jit, REG_0, tjit->func_meta_off, meta);
cur_cookie--;
}
- if (invoke_bpf_prog(tjit, m, tl->links[i], save_ret))
+ if (invoke_bpf_prog(tjit, m, tn->nodes[i], save_ret))
return -EINVAL;
}
@@ -2651,12 +2651,12 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
struct bpf_tramp_jit *tjit,
const struct btf_func_model *m,
u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
int nr_bpf_args, nr_reg_args, nr_stack_args;
int cookie_cnt, cookie_off, fsession_cnt;
struct bpf_jit *jit = &tjit->common;
@@ -2693,8 +2693,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
return -ENOTSUPP;
}
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
- fsession_cnt = bpf_fsession_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
+ fsession_cnt = bpf_fsession_cnt(tnodes);
/*
* Calculate the stack layout.
@@ -2829,7 +2829,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
func_meta, cookie_off))
return -EINVAL;
- if (fmod_ret->nr_links) {
+ if (fmod_ret->nr_nodes) {
/*
* retval = 0;
*/
@@ -2838,8 +2838,8 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
_EMIT6(0xd707f000 | tjit->retval_off,
0xf000 | tjit->retval_off);
- for (i = 0; i < fmod_ret->nr_links; i++) {
- if (invoke_bpf_prog(tjit, m, fmod_ret->links[i], true))
+ for (i = 0; i < fmod_ret->nr_nodes; i++) {
+ if (invoke_bpf_prog(tjit, m, fmod_ret->nodes[i], true))
return -EINVAL;
/*
@@ -2964,7 +2964,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im,
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *orig_call)
+ struct bpf_tramp_nodes *tnodes, void *orig_call)
{
struct bpf_tramp_image im;
struct bpf_tramp_jit tjit;
@@ -2973,14 +2973,14 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
memset(&tjit, 0, sizeof(tjit));
ret = __arch_prepare_bpf_trampoline(&im, &tjit, m, flags,
- tlinks, orig_call);
+ tnodes, orig_call);
return ret < 0 ? ret : tjit.common.prg;
}
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image,
void *image_end, const struct btf_func_model *m,
- u32 flags, struct bpf_tramp_links *tlinks,
+ u32 flags, struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
struct bpf_tramp_jit tjit;
@@ -2989,7 +2989,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image,
/* Compute offsets, check whether the code fits. */
memset(&tjit, 0, sizeof(tjit));
ret = __arch_prepare_bpf_trampoline(im, &tjit, m, flags,
- tlinks, func_addr);
+ tnodes, func_addr);
if (ret < 0)
return ret;
@@ -3003,7 +3003,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image,
tjit.common.prg = 0;
tjit.common.prg_buf = image;
ret = __arch_prepare_bpf_trampoline(im, &tjit, m, flags,
- tlinks, func_addr);
+ tnodes, func_addr);
return ret < 0 ? ret : tjit.common.prg;
}
diff --git a/arch/x86/net/bpf_jit_comp.c b/arch/x86/net/bpf_jit_comp.c
index a0c541a441cf..054e043ffcd2 100644
--- a/arch/x86/net/bpf_jit_comp.c
+++ b/arch/x86/net/bpf_jit_comp.c
@@ -3104,15 +3104,15 @@ static void restore_regs(const struct btf_func_model *m, u8 **prog,
}
static int invoke_bpf_prog(const struct btf_func_model *m, u8 **pprog,
- struct bpf_tramp_link *l, int stack_size,
+ struct bpf_tramp_node *node, int stack_size,
int run_ctx_off, bool save_ret,
void *image, void *rw_image)
{
u8 *prog = *pprog;
u8 *jmp_insn;
int ctx_cookie_off = offsetof(struct bpf_tramp_run_ctx, bpf_cookie);
- struct bpf_prog *p = l->link.prog;
- u64 cookie = l->cookie;
+ struct bpf_prog *p = node->link->prog;
+ u64 cookie = node->cookie;
/* mov rdi, cookie */
emit_mov_imm64(&prog, BPF_REG_1, (long) cookie >> 32, (u32) (long) cookie);
@@ -3219,7 +3219,7 @@ static int emit_cond_near_jump(u8 **pprog, void *func, void *ip, u8 jmp_cond)
}
static int invoke_bpf(const struct btf_func_model *m, u8 **pprog,
- struct bpf_tramp_links *tl, int stack_size,
+ struct bpf_tramp_nodes *tl, int stack_size,
int run_ctx_off, int func_meta_off, bool save_ret,
void *image, void *rw_image, u64 func_meta,
int cookie_off)
@@ -3227,13 +3227,13 @@ static int invoke_bpf(const struct btf_func_model *m, u8 **pprog,
int i, cur_cookie = (cookie_off - stack_size) / 8;
u8 *prog = *pprog;
- for (i = 0; i < tl->nr_links; i++) {
- if (tl->links[i]->link.prog->call_session_cookie) {
+ for (i = 0; i < tl->nr_nodes; i++) {
+ if (tl->nodes[i]->link->prog->call_session_cookie) {
emit_store_stack_imm64(&prog, BPF_REG_0, -func_meta_off,
func_meta | (cur_cookie << BPF_TRAMP_COOKIE_INDEX_SHIFT));
cur_cookie--;
}
- if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size,
+ if (invoke_bpf_prog(m, &prog, tl->nodes[i], stack_size,
run_ctx_off, save_ret, image, rw_image))
return -EINVAL;
}
@@ -3242,7 +3242,7 @@ static int invoke_bpf(const struct btf_func_model *m, u8 **pprog,
}
static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
- struct bpf_tramp_links *tl, int stack_size,
+ struct bpf_tramp_nodes *tl, int stack_size,
int run_ctx_off, u8 **branches,
void *image, void *rw_image)
{
@@ -3254,8 +3254,8 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
*/
emit_mov_imm32(&prog, false, BPF_REG_0, 0);
emit_stx(&prog, BPF_DW, BPF_REG_FP, BPF_REG_0, -8);
- for (i = 0; i < tl->nr_links; i++) {
- if (invoke_bpf_prog(m, &prog, tl->links[i], stack_size, run_ctx_off, true,
+ for (i = 0; i < tl->nr_nodes; i++) {
+ if (invoke_bpf_prog(m, &prog, tl->nodes[i], stack_size, run_ctx_off, true,
image, rw_image))
return -EINVAL;
@@ -3346,14 +3346,14 @@ static int invoke_bpf_mod_ret(const struct btf_func_model *m, u8 **pprog,
static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_image,
void *rw_image_end, void *image,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
int i, ret, nr_regs = m->nr_args, stack_size = 0;
int regs_off, func_meta_off, ip_off, run_ctx_off, arg_stack_off, rbx_off;
- struct bpf_tramp_links *fentry = &tlinks[BPF_TRAMP_FENTRY];
- struct bpf_tramp_links *fexit = &tlinks[BPF_TRAMP_FEXIT];
- struct bpf_tramp_links *fmod_ret = &tlinks[BPF_TRAMP_MODIFY_RETURN];
+ struct bpf_tramp_nodes *fentry = &tnodes[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes *fexit = &tnodes[BPF_TRAMP_FEXIT];
+ struct bpf_tramp_nodes *fmod_ret = &tnodes[BPF_TRAMP_MODIFY_RETURN];
void *orig_call = func_addr;
int cookie_off, cookie_cnt;
u8 **branches = NULL;
@@ -3425,7 +3425,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
ip_off = stack_size;
- cookie_cnt = bpf_fsession_cookie_cnt(tlinks);
+ cookie_cnt = bpf_fsession_cookie_cnt(tnodes);
/* room for session cookies */
stack_size += cookie_cnt * 8;
cookie_off = stack_size;
@@ -3518,7 +3518,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
}
}
- if (bpf_fsession_cnt(tlinks)) {
+ if (bpf_fsession_cnt(tnodes)) {
/* clear all the session cookies' value */
for (int i = 0; i < cookie_cnt; i++)
emit_store_stack_imm64(&prog, BPF_REG_0, -cookie_off + 8 * i, 0);
@@ -3526,15 +3526,15 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
emit_store_stack_imm64(&prog, BPF_REG_0, -8, 0);
}
- if (fentry->nr_links) {
+ if (fentry->nr_nodes) {
if (invoke_bpf(m, &prog, fentry, regs_off, run_ctx_off, func_meta_off,
flags & BPF_TRAMP_F_RET_FENTRY_RET, image, rw_image,
func_meta, cookie_off))
return -EINVAL;
}
- if (fmod_ret->nr_links) {
- branches = kcalloc(fmod_ret->nr_links, sizeof(u8 *),
+ if (fmod_ret->nr_nodes) {
+ branches = kcalloc(fmod_ret->nr_nodes, sizeof(u8 *),
GFP_KERNEL);
if (!branches)
return -ENOMEM;
@@ -3573,7 +3573,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
emit_nops(&prog, X86_PATCH_SIZE);
}
- if (fmod_ret->nr_links) {
+ if (fmod_ret->nr_nodes) {
/* From Intel 64 and IA-32 Architectures Optimization
* Reference Manual, 3.4.1.4 Code Alignment, Assembly/Compiler
* Coding Rule 11: All branch targets should be 16-byte
@@ -3583,7 +3583,7 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
/* Update the branches saved in invoke_bpf_mod_ret with the
* aligned address of do_fexit.
*/
- for (i = 0; i < fmod_ret->nr_links; i++) {
+ for (i = 0; i < fmod_ret->nr_nodes; i++) {
emit_cond_near_jump(&branches[i], image + (prog - (u8 *)rw_image),
image + (branches[i] - (u8 *)rw_image), X86_JNE);
}
@@ -3591,10 +3591,10 @@ static int __arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *rw_im
/* set the "is_return" flag for fsession */
func_meta |= (1ULL << BPF_TRAMP_IS_RETURN_SHIFT);
- if (bpf_fsession_cnt(tlinks))
+ if (bpf_fsession_cnt(tnodes))
emit_store_stack_imm64(&prog, BPF_REG_0, -func_meta_off, func_meta);
- if (fexit->nr_links) {
+ if (fexit->nr_nodes) {
if (invoke_bpf(m, &prog, fexit, regs_off, run_ctx_off, func_meta_off,
false, image, rw_image, func_meta, cookie_off)) {
ret = -EINVAL;
@@ -3668,7 +3668,7 @@ int arch_protect_bpf_trampoline(void *image, unsigned int size)
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
void *rw_image, *tmp;
@@ -3683,7 +3683,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
return -ENOMEM;
ret = __arch_prepare_bpf_trampoline(im, rw_image, rw_image + size, image, m,
- flags, tlinks, func_addr);
+ flags, tnodes, func_addr);
if (ret < 0)
goto out;
@@ -3696,7 +3696,7 @@ int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *i
}
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
struct bpf_tramp_image im;
void *image;
@@ -3714,7 +3714,7 @@ int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
return -ENOMEM;
ret = __arch_prepare_bpf_trampoline(&im, image, image + PAGE_SIZE, image,
- m, flags, tlinks, func_addr);
+ m, flags, tnodes, func_addr);
bpf_jit_free_exec(image);
return ret;
}
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index db89b3a591fa..36ee2a06eb15 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1249,9 +1249,9 @@ enum {
#define BPF_TRAMP_COOKIE_INDEX_SHIFT 8
#define BPF_TRAMP_IS_RETURN_SHIFT 63
-struct bpf_tramp_links {
- struct bpf_tramp_link *links[BPF_MAX_TRAMP_LINKS];
- int nr_links;
+struct bpf_tramp_nodes {
+ struct bpf_tramp_node *nodes[BPF_MAX_TRAMP_LINKS];
+ int nr_nodes;
};
struct bpf_tramp_run_ctx;
@@ -1279,13 +1279,13 @@ struct bpf_tramp_run_ctx;
struct bpf_tramp_image;
int arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr);
void *arch_alloc_bpf_trampoline(unsigned int size);
void arch_free_bpf_trampoline(void *image, unsigned int size);
int __must_check arch_protect_bpf_trampoline(void *image, unsigned int size);
int arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr);
+ struct bpf_tramp_nodes *tnodes, void *func_addr);
u64 notrace __bpf_prog_enter_sleepable_recur(struct bpf_prog *prog,
struct bpf_tramp_run_ctx *run_ctx);
@@ -1469,10 +1469,10 @@ static inline int bpf_dynptr_check_off_len(const struct bpf_dynptr_kern *ptr, u6
}
#ifdef CONFIG_BPF_JIT
-int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
+int bpf_trampoline_link_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog);
-int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
+int bpf_trampoline_unlink_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog);
struct bpf_trampoline *bpf_trampoline_get(u64 key,
@@ -1559,13 +1559,13 @@ bool bpf_insn_is_indirect_target(const struct bpf_verifier_env *env, const struc
int insn_idx);
u16 bpf_out_stack_arg_cnt(const struct bpf_verifier_env *env, const struct bpf_prog *prog);
#else
-static inline int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
+static inline int bpf_trampoline_link_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog)
{
return -ENOTSUPP;
}
-static inline int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
+static inline int bpf_trampoline_unlink_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog)
{
@@ -1889,12 +1889,17 @@ struct bpf_link_ops {
__poll_t (*poll)(struct file *file, struct poll_table_struct *pts);
};
-struct bpf_tramp_link {
- struct bpf_link link;
+struct bpf_tramp_node {
+ struct bpf_link *link;
struct hlist_node tramp_hlist;
u64 cookie;
};
+struct bpf_tramp_link {
+ struct bpf_link link;
+ struct bpf_tramp_node node;
+};
+
struct bpf_shim_tramp_link {
struct bpf_tramp_link link;
struct bpf_trampoline *trampoline;
@@ -2112,8 +2117,8 @@ void bpf_struct_ops_put(const void *kdata);
int bpf_struct_ops_supported(const struct bpf_struct_ops *st_ops, u32 moff);
int bpf_struct_ops_map_sys_lookup_elem(struct bpf_map *map, void *key,
void *value);
-int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
- struct bpf_tramp_link *link,
+int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_nodes *tnodes,
+ struct bpf_tramp_node *node,
const struct btf_func_model *model,
void *stub_func,
void **image, u32 *image_off,
@@ -2208,31 +2213,31 @@ static inline void bpf_struct_ops_desc_release(struct bpf_struct_ops_desc *st_op
#endif
-static inline int bpf_fsession_cnt(struct bpf_tramp_links *links)
+static inline int bpf_fsession_cnt(struct bpf_tramp_nodes *nodes)
{
- struct bpf_tramp_links fentries = links[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes fentries = nodes[BPF_TRAMP_FENTRY];
int cnt = 0;
- for (int i = 0; i < links[BPF_TRAMP_FENTRY].nr_links; i++) {
- if (fentries.links[i]->link.prog->expected_attach_type == BPF_TRACE_FSESSION)
+ for (int i = 0; i < nodes[BPF_TRAMP_FENTRY].nr_nodes; i++) {
+ if (fentries.nodes[i]->link->prog->expected_attach_type == BPF_TRACE_FSESSION)
cnt++;
}
return cnt;
}
-static inline bool bpf_prog_calls_session_cookie(struct bpf_tramp_link *link)
+static inline bool bpf_prog_calls_session_cookie(struct bpf_tramp_node *node)
{
- return link->link.prog->call_session_cookie;
+ return node->link->prog->call_session_cookie;
}
-static inline int bpf_fsession_cookie_cnt(struct bpf_tramp_links *links)
+static inline int bpf_fsession_cookie_cnt(struct bpf_tramp_nodes *nodes)
{
- struct bpf_tramp_links fentries = links[BPF_TRAMP_FENTRY];
+ struct bpf_tramp_nodes fentries = nodes[BPF_TRAMP_FENTRY];
int cnt = 0;
- for (int i = 0; i < links[BPF_TRAMP_FENTRY].nr_links; i++) {
- if (bpf_prog_calls_session_cookie(fentries.links[i]))
+ for (int i = 0; i < nodes[BPF_TRAMP_FENTRY].nr_nodes; i++) {
+ if (bpf_prog_calls_session_cookie(fentries.nodes[i]))
cnt++;
}
@@ -2780,6 +2785,9 @@ void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type,
const struct bpf_link_ops *ops, struct bpf_prog *prog,
enum bpf_attach_type attach_type, bool sleepable);
+void bpf_tramp_link_init(struct bpf_tramp_link *link, enum bpf_link_type type,
+ const struct bpf_link_ops *ops, struct bpf_prog *prog,
+ enum bpf_attach_type attach_type, u64 cookie);
int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer);
int bpf_link_settle(struct bpf_link_primer *primer);
void bpf_link_cleanup(struct bpf_link_primer *primer);
@@ -3203,6 +3211,12 @@ static inline void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_
{
}
+static inline void bpf_tramp_link_init(struct bpf_tramp_link *link, enum bpf_link_type type,
+ const struct bpf_link_ops *ops, struct bpf_prog *prog,
+ enum bpf_attach_type attach_type, u64 cookie)
+{
+}
+
static inline int bpf_link_prime(struct bpf_link *link,
struct bpf_link_primer *primer)
{
diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c
index 5e51c1211673..51b16e5f5534 100644
--- a/kernel/bpf/bpf_struct_ops.c
+++ b/kernel/bpf/bpf_struct_ops.c
@@ -594,8 +594,8 @@ const struct bpf_link_ops bpf_struct_ops_link_lops = {
.dealloc = bpf_struct_ops_link_dealloc,
};
-int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
- struct bpf_tramp_link *link,
+int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_nodes *tnodes,
+ struct bpf_tramp_node *node,
const struct btf_func_model *model,
void *stub_func,
void **_image, u32 *_image_off,
@@ -605,13 +605,13 @@ int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
void *image = *_image;
int size;
- tlinks[BPF_TRAMP_FENTRY].links[0] = link;
- tlinks[BPF_TRAMP_FENTRY].nr_links = 1;
+ tnodes[BPF_TRAMP_FENTRY].nodes[0] = node;
+ tnodes[BPF_TRAMP_FENTRY].nr_nodes = 1;
if (model->ret_size > 0)
flags |= BPF_TRAMP_F_RET_FENTRY_RET;
- size = arch_bpf_trampoline_size(model, flags, tlinks, stub_func);
+ size = arch_bpf_trampoline_size(model, flags, tnodes, stub_func);
if (size <= 0)
return size ? : -EFAULT;
@@ -628,7 +628,7 @@ int bpf_struct_ops_prepare_trampoline(struct bpf_tramp_links *tlinks,
size = arch_prepare_bpf_trampoline(NULL, image + image_off,
image + image_off + size,
- model, flags, tlinks, stub_func);
+ model, flags, tnodes, stub_func);
if (size <= 0) {
if (image != *_image)
bpf_struct_ops_image_free(image);
@@ -693,7 +693,7 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
const struct btf_type *module_type;
const struct btf_member *member;
const struct btf_type *t = st_ops_desc->type;
- struct bpf_tramp_links *tlinks;
+ struct bpf_tramp_nodes *tnodes;
void *udata, *kdata;
int prog_fd, err;
u32 i, trampoline_start, image_off = 0;
@@ -720,8 +720,8 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
if (uvalue->common.state || refcount_read(&uvalue->common.refcnt))
return -EINVAL;
- tlinks = kzalloc_objs(*tlinks, BPF_TRAMP_MAX);
- if (!tlinks)
+ tnodes = kzalloc_objs(*tnodes, BPF_TRAMP_MAX);
+ if (!tnodes)
return -ENOMEM;
uvalue = (struct bpf_struct_ops_value *)st_map->uvalue;
@@ -817,8 +817,9 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
err = -ENOMEM;
goto reset_unlock;
}
- bpf_link_init(&link->link, BPF_LINK_TYPE_STRUCT_OPS,
- &bpf_struct_ops_link_lops, prog, prog->expected_attach_type);
+ bpf_tramp_link_init(link, BPF_LINK_TYPE_STRUCT_OPS,
+ &bpf_struct_ops_link_lops, prog, prog->expected_attach_type, 0);
+
*plink++ = &link->link;
/* Poison pointer on error instead of return for backward compatibility */
@@ -832,7 +833,7 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
*pksym++ = ksym;
trampoline_start = image_off;
- err = bpf_struct_ops_prepare_trampoline(tlinks, link,
+ err = bpf_struct_ops_prepare_trampoline(tnodes, &link->node,
&st_ops->func_models[i],
*(void **)(st_ops->cfi_stubs + moff),
&image, &image_off,
@@ -911,7 +912,7 @@ static long bpf_struct_ops_map_update_elem(struct bpf_map *map, void *key,
memset(uvalue, 0, map->value_size);
memset(kvalue, 0, map->value_size);
unlock:
- kfree(tlinks);
+ kfree(tnodes);
mutex_unlock(&st_map->lock);
if (!err)
bpf_struct_ops_map_add_ksyms(st_map);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 8d4ea700aac6..b0770b5203e5 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3244,6 +3244,15 @@ void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
bpf_link_init_sleepable(link, type, ops, prog, attach_type, false);
}
+void bpf_tramp_link_init(struct bpf_tramp_link *link, enum bpf_link_type type,
+ const struct bpf_link_ops *ops, struct bpf_prog *prog,
+ enum bpf_attach_type attach_type, u64 cookie)
+{
+ bpf_link_init(&link->link, type, ops, prog, attach_type);
+ link->node.link = &link->link;
+ link->node.cookie = cookie;
+}
+
static void bpf_link_free_id(int id)
{
if (!id)
@@ -3551,7 +3560,7 @@ static void bpf_tracing_link_release(struct bpf_link *link)
struct bpf_tracing_link *tr_link =
container_of(link, struct bpf_tracing_link, link.link);
- WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link,
+ WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link.node,
tr_link->trampoline,
tr_link->tgt_prog));
@@ -3564,8 +3573,7 @@ static void bpf_tracing_link_release(struct bpf_link *link)
static void bpf_tracing_link_dealloc(struct bpf_link *link)
{
- struct bpf_tracing_link *tr_link =
- container_of(link, struct bpf_tracing_link, link.link);
+ struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link);
kfree(tr_link);
}
@@ -3573,8 +3581,8 @@ static void bpf_tracing_link_dealloc(struct bpf_link *link)
static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
struct seq_file *seq)
{
- struct bpf_tracing_link *tr_link =
- container_of(link, struct bpf_tracing_link, link.link);
+ struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link);
+
u32 target_btf_id, target_obj_id;
bpf_trampoline_unpack_key(tr_link->trampoline->key,
@@ -3587,17 +3595,16 @@ static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
link->attach_type,
target_obj_id,
target_btf_id,
- tr_link->link.cookie);
+ tr_link->link.node.cookie);
}
static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
struct bpf_link_info *info)
{
- struct bpf_tracing_link *tr_link =
- container_of(link, struct bpf_tracing_link, link.link);
+ struct bpf_tracing_link *tr_link = container_of(link, struct bpf_tracing_link, link.link);
info->tracing.attach_type = link->attach_type;
- info->tracing.cookie = tr_link->link.cookie;
+ info->tracing.cookie = tr_link->link.node.cookie;
bpf_trampoline_unpack_key(tr_link->trampoline->key,
&info->tracing.target_obj_id,
&info->tracing.target_btf_id);
@@ -3684,9 +3691,9 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
fslink = kzalloc_obj(*fslink, GFP_USER);
if (fslink) {
- bpf_link_init(&fslink->fexit.link, BPF_LINK_TYPE_TRACING,
- &bpf_tracing_link_lops, prog, attach_type);
- fslink->fexit.cookie = bpf_cookie;
+ bpf_tramp_link_init(&fslink->fexit, BPF_LINK_TYPE_TRACING,
+ &bpf_tracing_link_lops, prog, attach_type,
+ bpf_cookie);
link = &fslink->link;
} else {
link = NULL;
@@ -3698,10 +3705,8 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
err = -ENOMEM;
goto out_put_prog;
}
- bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING,
- &bpf_tracing_link_lops, prog, attach_type);
-
- link->link.cookie = bpf_cookie;
+ bpf_tramp_link_init(&link->link, BPF_LINK_TYPE_TRACING,
+ &bpf_tracing_link_lops, prog, attach_type, bpf_cookie);
mutex_lock(&prog->aux->dst_mutex);
@@ -3804,7 +3809,7 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
if (err)
goto out_unlock;
- err = bpf_trampoline_link_prog(&link->link, tr, tgt_prog);
+ err = bpf_trampoline_link_prog(&link->link.node, tr, tgt_prog);
if (err) {
bpf_link_cleanup(&link_primer);
link = NULL;
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 70724b0d8fb8..7f71f929fa6f 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -502,30 +502,29 @@ static const struct bpf_trampoline_ops trampoline_ops = {
.modify_fentry = modify_fentry,
};
-static struct bpf_tramp_links *
+static struct bpf_tramp_nodes *
bpf_trampoline_get_progs(const struct bpf_trampoline *tr, int *total, bool *ip_arg)
{
- struct bpf_tramp_link *link;
- struct bpf_tramp_links *tlinks;
- struct bpf_tramp_link **links;
+ struct bpf_tramp_node *node, **nodes;
+ struct bpf_tramp_nodes *tnodes;
int kind;
*total = 0;
- tlinks = kzalloc_objs(*tlinks, BPF_TRAMP_MAX);
- if (!tlinks)
+ tnodes = kzalloc_objs(*tnodes, BPF_TRAMP_MAX);
+ if (!tnodes)
return ERR_PTR(-ENOMEM);
for (kind = 0; kind < BPF_TRAMP_MAX; kind++) {
- tlinks[kind].nr_links = tr->progs_cnt[kind];
+ tnodes[kind].nr_nodes = tr->progs_cnt[kind];
*total += tr->progs_cnt[kind];
- links = tlinks[kind].links;
+ nodes = tnodes[kind].nodes;
- hlist_for_each_entry(link, &tr->progs_hlist[kind], tramp_hlist) {
- *ip_arg |= link->link.prog->call_get_func_ip;
- *links++ = link;
+ hlist_for_each_entry(node, &tr->progs_hlist[kind], tramp_hlist) {
+ *ip_arg |= node->link->prog->call_get_func_ip;
+ *nodes++ = node;
}
}
- return tlinks;
+ return tnodes;
}
static void bpf_tramp_image_free(struct bpf_tramp_image *im)
@@ -673,14 +672,14 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
const struct bpf_trampoline_ops *ops, void *data)
{
struct bpf_tramp_image *im;
- struct bpf_tramp_links *tlinks;
+ struct bpf_tramp_nodes *tnodes;
u32 orig_flags = tr->flags;
bool ip_arg = false;
int err, total, size;
- tlinks = bpf_trampoline_get_progs(tr, &total, &ip_arg);
- if (IS_ERR(tlinks))
- return PTR_ERR(tlinks);
+ tnodes = bpf_trampoline_get_progs(tr, &total, &ip_arg);
+ if (IS_ERR(tnodes))
+ return PTR_ERR(tnodes);
if (total == 0) {
err = ops->unregister_fentry(tr, orig_flags, data);
@@ -690,8 +689,8 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
/* clear all bits except SHARE_IPMODIFY and TAIL_CALL_CTX */
tr->flags &= (BPF_TRAMP_F_SHARE_IPMODIFY | BPF_TRAMP_F_TAIL_CALL_CTX);
- if (tlinks[BPF_TRAMP_FEXIT].nr_links ||
- tlinks[BPF_TRAMP_MODIFY_RETURN].nr_links) {
+ if (tnodes[BPF_TRAMP_FEXIT].nr_nodes ||
+ tnodes[BPF_TRAMP_MODIFY_RETURN].nr_nodes) {
/* NOTE: BPF_TRAMP_F_RESTORE_REGS and BPF_TRAMP_F_SKIP_FRAME
* should not be set together.
*/
@@ -722,7 +721,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
#endif
size = arch_bpf_trampoline_size(&tr->func.model, tr->flags,
- tlinks, tr->func.addr);
+ tnodes, tr->func.addr);
if (size < 0) {
err = size;
goto out;
@@ -740,7 +739,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
}
err = arch_prepare_bpf_trampoline(im, im->image, im->image + size,
- &tr->func.model, tr->flags, tlinks,
+ &tr->func.model, tr->flags, tnodes,
tr->func.addr);
if (err < 0)
goto out_free;
@@ -774,7 +773,7 @@ static int bpf_trampoline_update(struct bpf_trampoline *tr, bool lock_direct_mut
/* If any error happens, restore previous flags */
if (err)
tr->flags = orig_flags;
- kfree(tlinks);
+ kfree(tnodes);
return err;
}
@@ -821,15 +820,15 @@ static int bpf_freplace_check_tgt_prog(struct bpf_prog *tgt_prog)
}
static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
- struct bpf_tramp_link *link,
+ struct bpf_tramp_node *node,
int cnt)
{
struct bpf_fsession_link *fslink = NULL;
enum bpf_tramp_prog_type kind;
- struct bpf_tramp_link *link_exiting;
+ struct bpf_tramp_node *node_existing;
struct hlist_head *prog_list;
- kind = bpf_attach_type_to_tramp(link->link.prog);
+ kind = bpf_attach_type_to_tramp(node->link->prog);
if (kind == BPF_TRAMP_FSESSION) {
prog_list = &tr->progs_hlist[BPF_TRAMP_FENTRY];
cnt++;
@@ -838,21 +837,21 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
}
if (cnt >= BPF_MAX_TRAMP_LINKS)
return -E2BIG;
- if (!hlist_unhashed(&link->tramp_hlist))
+ if (!hlist_unhashed(&node->tramp_hlist))
/* prog already linked */
return -EBUSY;
- hlist_for_each_entry(link_exiting, prog_list, tramp_hlist) {
- if (link_exiting->link.prog != link->link.prog)
+ hlist_for_each_entry(node_existing, prog_list, tramp_hlist) {
+ if (node_existing->link->prog != node->link->prog)
continue;
/* prog already linked */
return -EBUSY;
}
- hlist_add_head(&link->tramp_hlist, prog_list);
+ hlist_add_head(&node->tramp_hlist, prog_list);
if (kind == BPF_TRAMP_FSESSION) {
tr->progs_cnt[BPF_TRAMP_FENTRY]++;
- fslink = container_of(link, struct bpf_fsession_link, link.link);
- hlist_add_head(&fslink->fexit.tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
+ fslink = container_of(node, struct bpf_fsession_link, link.link.node);
+ hlist_add_head(&fslink->fexit.node.tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
tr->progs_cnt[BPF_TRAMP_FEXIT]++;
} else {
tr->progs_cnt[kind]++;
@@ -861,23 +860,23 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
}
static void bpf_trampoline_remove_prog(struct bpf_trampoline *tr,
- struct bpf_tramp_link *link)
+ struct bpf_tramp_node *node)
{
struct bpf_fsession_link *fslink;
enum bpf_tramp_prog_type kind;
- kind = bpf_attach_type_to_tramp(link->link.prog);
+ kind = bpf_attach_type_to_tramp(node->link->prog);
if (kind == BPF_TRAMP_FSESSION) {
- fslink = container_of(link, struct bpf_fsession_link, link.link);
- hlist_del_init(&fslink->fexit.tramp_hlist);
+ fslink = container_of(node, struct bpf_fsession_link, link.link.node);
+ hlist_del_init(&fslink->fexit.node.tramp_hlist);
tr->progs_cnt[BPF_TRAMP_FEXIT]--;
kind = BPF_TRAMP_FENTRY;
}
- hlist_del_init(&link->tramp_hlist);
+ hlist_del_init(&node->tramp_hlist);
tr->progs_cnt[kind]--;
}
-static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
+static int __bpf_trampoline_link_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog,
const struct bpf_trampoline_ops *ops,
@@ -887,7 +886,7 @@ static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
int err = 0;
int cnt = 0, i;
- kind = bpf_attach_type_to_tramp(link->link.prog);
+ kind = bpf_attach_type_to_tramp(node->link->prog);
if (tr->extension_prog)
/* cannot attach fentry/fexit if extension prog is attached.
* cannot overwrite extension prog either.
@@ -904,33 +903,33 @@ static int __bpf_trampoline_link_prog(struct bpf_tramp_link *link,
err = bpf_freplace_check_tgt_prog(tgt_prog);
if (err)
return err;
- tr->extension_prog = link->link.prog;
+ tr->extension_prog = node->link->prog;
return bpf_arch_text_poke(tr->func.addr, BPF_MOD_NOP,
BPF_MOD_JUMP, NULL,
- link->link.prog->bpf_func);
+ node->link->prog->bpf_func);
}
- err = bpf_trampoline_add_prog(tr, link, cnt);
+ err = bpf_trampoline_add_prog(tr, node, cnt);
if (err)
return err;
err = bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
if (err)
- bpf_trampoline_remove_prog(tr, link);
+ bpf_trampoline_remove_prog(tr, node);
return err;
}
-int bpf_trampoline_link_prog(struct bpf_tramp_link *link,
+int bpf_trampoline_link_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog)
{
int err;
trampoline_lock(tr);
- err = __bpf_trampoline_link_prog(link, tr, tgt_prog, &trampoline_ops, NULL);
+ err = __bpf_trampoline_link_prog(node, tr, tgt_prog, &trampoline_ops, NULL);
trampoline_unlock(tr);
return err;
}
-static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
+static int __bpf_trampoline_unlink_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog,
const struct bpf_trampoline_ops *ops,
@@ -939,7 +938,7 @@ static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
enum bpf_tramp_prog_type kind;
int err;
- kind = bpf_attach_type_to_tramp(link->link.prog);
+ kind = bpf_attach_type_to_tramp(node->link->prog);
if (kind == BPF_TRAMP_REPLACE) {
WARN_ON_ONCE(!tr->extension_prog);
err = bpf_arch_text_poke(tr->func.addr, BPF_MOD_JUMP,
@@ -950,19 +949,19 @@ static int __bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
tgt_prog->aux->is_extended = false;
return err;
}
- bpf_trampoline_remove_prog(tr, link);
+ bpf_trampoline_remove_prog(tr, node);
return bpf_trampoline_update(tr, true /* lock_direct_mutex */, ops, data);
}
/* bpf_trampoline_unlink_prog() should never fail. */
-int bpf_trampoline_unlink_prog(struct bpf_tramp_link *link,
+int bpf_trampoline_unlink_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
struct bpf_prog *tgt_prog)
{
int err;
trampoline_lock(tr);
- err = __bpf_trampoline_unlink_prog(link, tr, tgt_prog, &trampoline_ops, NULL);
+ err = __bpf_trampoline_unlink_prog(node, tr, tgt_prog, &trampoline_ops, NULL);
trampoline_unlock(tr);
return err;
}
@@ -977,7 +976,7 @@ static void bpf_shim_tramp_link_release(struct bpf_link *link)
if (!shim_link->trampoline)
return;
- WARN_ON_ONCE(bpf_trampoline_unlink_prog(&shim_link->link, shim_link->trampoline, NULL));
+ WARN_ON_ONCE(bpf_trampoline_unlink_prog(&shim_link->link.node, shim_link->trampoline, NULL));
bpf_trampoline_put(shim_link->trampoline);
}
@@ -1023,8 +1022,8 @@ static struct bpf_shim_tramp_link *cgroup_shim_alloc(const struct bpf_prog *prog
p->type = BPF_PROG_TYPE_LSM;
p->expected_attach_type = BPF_LSM_MAC;
bpf_prog_inc(p);
- bpf_link_init(&shim_link->link.link, BPF_LINK_TYPE_UNSPEC,
- &bpf_shim_tramp_link_lops, p, attach_type);
+ bpf_tramp_link_init(&shim_link->link, BPF_LINK_TYPE_UNSPEC,
+ &bpf_shim_tramp_link_lops, p, attach_type, 0);
bpf_cgroup_atype_get(p->aux->attach_btf_id, cgroup_atype);
return shim_link;
@@ -1033,15 +1032,15 @@ static struct bpf_shim_tramp_link *cgroup_shim_alloc(const struct bpf_prog *prog
static struct bpf_shim_tramp_link *cgroup_shim_find(struct bpf_trampoline *tr,
bpf_func_t bpf_func)
{
- struct bpf_tramp_link *link;
+ struct bpf_tramp_node *node;
int kind;
for (kind = 0; kind < BPF_TRAMP_MAX; kind++) {
- hlist_for_each_entry(link, &tr->progs_hlist[kind], tramp_hlist) {
- struct bpf_prog *p = link->link.prog;
+ hlist_for_each_entry(node, &tr->progs_hlist[kind], tramp_hlist) {
+ struct bpf_prog *p = node->link->prog;
if (p->bpf_func == bpf_func)
- return container_of(link, struct bpf_shim_tramp_link, link);
+ return container_of(node, struct bpf_shim_tramp_link, link.node);
}
}
@@ -1091,7 +1090,7 @@ int bpf_trampoline_link_cgroup_shim(struct bpf_prog *prog,
goto err;
}
- err = __bpf_trampoline_link_prog(&shim_link->link, tr, NULL, &trampoline_ops, NULL);
+ err = __bpf_trampoline_link_prog(&shim_link->link.node, tr, NULL, &trampoline_ops, NULL);
if (err)
goto err;
@@ -1406,7 +1405,7 @@ bpf_trampoline_exit_t bpf_trampoline_exit(const struct bpf_prog *prog)
int __weak
arch_prepare_bpf_trampoline(struct bpf_tramp_image *im, void *image, void *image_end,
const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks,
+ struct bpf_tramp_nodes *tnodes,
void *func_addr)
{
return -ENOTSUPP;
@@ -1440,7 +1439,7 @@ int __weak arch_protect_bpf_trampoline(void *image, unsigned int size)
}
int __weak arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
- struct bpf_tramp_links *tlinks, void *func_addr)
+ struct bpf_tramp_nodes *tnodes, void *func_addr)
{
return -ENOTSUPP;
}
diff --git a/net/bpf/bpf_dummy_struct_ops.c b/net/bpf/bpf_dummy_struct_ops.c
index ae5a54c350b9..191a6b3ee254 100644
--- a/net/bpf/bpf_dummy_struct_ops.c
+++ b/net/bpf/bpf_dummy_struct_ops.c
@@ -132,7 +132,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
const struct bpf_struct_ops *st_ops = &bpf_bpf_dummy_ops;
const struct btf_type *func_proto;
struct bpf_dummy_ops_test_args *args;
- struct bpf_tramp_links *tlinks = NULL;
+ struct bpf_tramp_nodes *tnodes = NULL;
struct bpf_tramp_link *link = NULL;
void *image = NULL;
unsigned int op_idx;
@@ -158,8 +158,8 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
if (err)
goto out;
- tlinks = kzalloc_objs(*tlinks, BPF_TRAMP_MAX);
- if (!tlinks) {
+ tnodes = kzalloc_objs(*tnodes, BPF_TRAMP_MAX);
+ if (!tnodes) {
err = -ENOMEM;
goto out;
}
@@ -171,11 +171,11 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
}
/* prog doesn't take the ownership of the reference from caller */
bpf_prog_inc(prog);
- bpf_link_init(&link->link, BPF_LINK_TYPE_STRUCT_OPS, &bpf_struct_ops_link_lops, prog,
- prog->expected_attach_type);
+ bpf_tramp_link_init(link, BPF_LINK_TYPE_STRUCT_OPS, &bpf_struct_ops_link_lops,
+ prog, prog->expected_attach_type, 0);
op_idx = prog->expected_attach_type;
- err = bpf_struct_ops_prepare_trampoline(tlinks, link,
+ err = bpf_struct_ops_prepare_trampoline(tnodes, &link->node,
&st_ops->func_models[op_idx],
&dummy_ops_test_ret_function,
&image, &image_off,
@@ -198,7 +198,7 @@ int bpf_struct_ops_test_run(struct bpf_prog *prog, const union bpf_attr *kattr,
bpf_struct_ops_image_free(image);
if (link)
bpf_link_put(&link->link);
- kfree(tlinks);
+ kfree(tnodes);
return err;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 09/29] bpf: Factor fsession link to use struct bpf_tramp_node
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (7 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 08/29] bpf: Add struct bpf_tramp_node object Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 10/29] bpf: Add multi tracing attach types Jiri Olsa
` (19 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Now that we split trampoline attachment object (bpf_tramp_node) from
the link object (bpf_tramp_link) we can use bpf_tramp_node as fsession's
fexit attachment object and get rid of the bpf_fsession_link object.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 6 +-----
kernel/bpf/syscall.c | 21 ++++++---------------
kernel/bpf/trampoline.c | 12 ++++++------
3 files changed, 13 insertions(+), 26 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 36ee2a06eb15..8f2c5e39cc80 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1907,15 +1907,11 @@ struct bpf_shim_tramp_link {
struct bpf_tracing_link {
struct bpf_tramp_link link;
+ struct bpf_tramp_node fexit;
struct bpf_trampoline *trampoline;
struct bpf_prog *tgt_prog;
};
-struct bpf_fsession_link {
- struct bpf_tracing_link link;
- struct bpf_tramp_link fexit;
-};
-
struct bpf_raw_tp_link {
struct bpf_link link;
struct bpf_raw_event_map *btp;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index b0770b5203e5..435ae6efe961 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3686,21 +3686,7 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
}
- if (prog->expected_attach_type == BPF_TRACE_FSESSION) {
- struct bpf_fsession_link *fslink;
-
- fslink = kzalloc_obj(*fslink, GFP_USER);
- if (fslink) {
- bpf_tramp_link_init(&fslink->fexit, BPF_LINK_TYPE_TRACING,
- &bpf_tracing_link_lops, prog, attach_type,
- bpf_cookie);
- link = &fslink->link;
- } else {
- link = NULL;
- }
- } else {
- link = kzalloc_obj(*link, GFP_USER);
- }
+ link = kzalloc_obj(*link, GFP_USER);
if (!link) {
err = -ENOMEM;
goto out_put_prog;
@@ -3708,6 +3694,11 @@ static int bpf_tracing_prog_attach(struct bpf_prog *prog,
bpf_tramp_link_init(&link->link, BPF_LINK_TYPE_TRACING,
&bpf_tracing_link_lops, prog, attach_type, bpf_cookie);
+ if (prog->expected_attach_type == BPF_TRACE_FSESSION) {
+ link->fexit.link = &link->link.link;
+ link->fexit.cookie = bpf_cookie;
+ }
+
mutex_lock(&prog->aux->dst_mutex);
/* There are a few possible cases here:
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 7f71f929fa6f..90c4cfd31b58 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -823,7 +823,7 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
struct bpf_tramp_node *node,
int cnt)
{
- struct bpf_fsession_link *fslink = NULL;
+ struct bpf_tracing_link *tr_link = NULL;
enum bpf_tramp_prog_type kind;
struct bpf_tramp_node *node_existing;
struct hlist_head *prog_list;
@@ -850,8 +850,8 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
hlist_add_head(&node->tramp_hlist, prog_list);
if (kind == BPF_TRAMP_FSESSION) {
tr->progs_cnt[BPF_TRAMP_FENTRY]++;
- fslink = container_of(node, struct bpf_fsession_link, link.link.node);
- hlist_add_head(&fslink->fexit.node.tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
+ tr_link = container_of(node, struct bpf_tracing_link, link.node);
+ hlist_add_head(&tr_link->fexit.tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
tr->progs_cnt[BPF_TRAMP_FEXIT]++;
} else {
tr->progs_cnt[kind]++;
@@ -862,13 +862,13 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
static void bpf_trampoline_remove_prog(struct bpf_trampoline *tr,
struct bpf_tramp_node *node)
{
- struct bpf_fsession_link *fslink;
+ struct bpf_tracing_link *tr_link;
enum bpf_tramp_prog_type kind;
kind = bpf_attach_type_to_tramp(node->link->prog);
if (kind == BPF_TRAMP_FSESSION) {
- fslink = container_of(node, struct bpf_fsession_link, link.link.node);
- hlist_del_init(&fslink->fexit.node.tramp_hlist);
+ tr_link = container_of(node, struct bpf_tracing_link, link.node);
+ hlist_del_init(&tr_link->fexit.tramp_hlist);
tr->progs_cnt[BPF_TRAMP_FEXIT]--;
kind = BPF_TRAMP_FENTRY;
}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 10/29] bpf: Add multi tracing attach types
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (8 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 09/29] bpf: Factor fsession link to use struct bpf_tramp_node Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 12:59 ` bot+bpf-ci
2026-05-27 11:39 ` [PATCHv6 bpf-next 11/29] bpf: Move sleepable verification code to btf_id_allow_sleepable Jiri Olsa
` (18 subsequent siblings)
28 siblings, 1 reply; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding new program attach types multi tracing attachment:
BPF_TRACE_FENTRY_MULTI
BPF_TRACE_FEXIT_MULTI
and their base support in verifier code.
Programs with such attach type will use specific link attachment
interface coming in following changes.
This was suggested by Andrii some (long) time ago and turned out
to be easier than having special program flag for that.
Bpf programs with such types have 'bpf_multi_func' function set as
their attach_btf_id and keep module reference when it's specified
by attach_prog_fd.
They are also accepted as sleepable programs during verification,
and the real validation for specific BTF_IDs/functions will happen
during the multi link attachment in following changes.
Suggested-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 5 +++++
include/linux/btf_ids.h | 1 +
include/uapi/linux/bpf.h | 2 ++
kernel/bpf/fixups.c | 1 +
kernel/bpf/syscall.c | 28 ++++++++++++++++++++----
kernel/bpf/trampoline.c | 5 ++++-
kernel/bpf/verifier.c | 40 +++++++++++++++++++++++++++++++++-
net/bpf/test_run.c | 2 ++
tools/include/uapi/linux/bpf.h | 2 ++
tools/lib/bpf/libbpf.c | 2 ++
10 files changed, 82 insertions(+), 6 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 8f2c5e39cc80..adae0674d329 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -2093,6 +2093,11 @@ static inline void bpf_prog_put_recursion_context(struct bpf_prog *prog)
#endif
}
+static inline bool is_tracing_multi(enum bpf_attach_type type)
+{
+ return type == BPF_TRACE_FENTRY_MULTI || type == BPF_TRACE_FEXIT_MULTI;
+}
+
#if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL)
/* This macro helps developer to register a struct_ops type and generate
* type information correctly. Developers should use this macro to register
diff --git a/include/linux/btf_ids.h b/include/linux/btf_ids.h
index af011db39ab3..8b5a9ee92513 100644
--- a/include/linux/btf_ids.h
+++ b/include/linux/btf_ids.h
@@ -284,5 +284,6 @@ extern u32 bpf_cgroup_btf_id[];
extern u32 bpf_local_storage_map_btf_id[];
extern u32 btf_bpf_map_id[];
extern u32 bpf_kmem_cache_btf_id[];
+extern u32 bpf_multi_func_btf_id[];
#endif
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index aec171ccb6ef..0cde0e2f3d4b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1155,6 +1155,8 @@ enum bpf_attach_type {
BPF_TRACE_KPROBE_SESSION,
BPF_TRACE_UPROBE_SESSION,
BPF_TRACE_FSESSION,
+ BPF_TRACE_FENTRY_MULTI,
+ BPF_TRACE_FEXIT_MULTI,
__MAX_BPF_ATTACH_TYPE
};
diff --git a/kernel/bpf/fixups.c b/kernel/bpf/fixups.c
index 12739add2dda..1d4ea0beb076 100644
--- a/kernel/bpf/fixups.c
+++ b/kernel/bpf/fixups.c
@@ -2186,6 +2186,7 @@ int bpf_do_misc_fixups(struct bpf_verifier_env *env)
insn->imm == BPF_FUNC_get_func_ret) {
if (eatype == BPF_TRACE_FEXIT ||
eatype == BPF_TRACE_FSESSION ||
+ eatype == BPF_TRACE_FEXIT_MULTI ||
eatype == BPF_MODIFY_RETURN) {
/* Load nr_args from ctx - 8 */
insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 435ae6efe961..27ad0c265c95 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -41,6 +41,7 @@
#include <linux/overflow.h>
#include <linux/cookie.h>
#include <linux/verification.h>
+#include <linux/btf_ids.h>
#include <net/netfilter/nf_bpf_link.h>
#include <net/netkit.h>
@@ -2692,7 +2693,8 @@ static int
bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
enum bpf_attach_type expected_attach_type,
struct btf *attach_btf, u32 btf_id,
- struct bpf_prog *dst_prog)
+ struct bpf_prog *dst_prog,
+ bool multi_func)
{
if (btf_id) {
if (btf_id > BTF_MAX_TYPE)
@@ -2712,6 +2714,14 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
}
}
+ if (multi_func) {
+ if (prog_type != BPF_PROG_TYPE_TRACING)
+ return -EINVAL;
+ if (!attach_btf || btf_id)
+ return -EINVAL;
+ return 0;
+ }
+
if (attach_btf && (!btf_id || dst_prog))
return -EINVAL;
@@ -2904,6 +2914,11 @@ static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog)
return 0;
}
+extern int bpf_multi_func(void);
+int __init __used bpf_multi_func(void) { return 0; }
+
+BTF_ID_LIST_GLOBAL_SINGLE(bpf_multi_func_btf_id, func, bpf_multi_func)
+
/* last field in 'union bpf_attr' used by this command */
#define BPF_PROG_LOAD_LAST_FIELD keyring_id
@@ -2916,6 +2931,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at
bool bpf_cap;
int err;
char license[128];
+ bool multi_func;
if (CHECK_ATTR(BPF_PROG_LOAD))
return -EINVAL;
@@ -2982,6 +2998,8 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at
if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON))
goto put_token;
+ multi_func = is_tracing_multi(attr->expected_attach_type);
+
/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
* or btf, we need to check which one it is
*/
@@ -3003,7 +3021,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at
goto put_token;
}
}
- } else if (attr->attach_btf_id) {
+ } else if (attr->attach_btf_id || multi_func) {
/* fall back to vmlinux BTF, if BTF type ID is specified */
attach_btf = bpf_get_btf_vmlinux();
if (IS_ERR(attach_btf)) {
@@ -3019,7 +3037,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at
if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
attach_btf, attr->attach_btf_id,
- dst_prog)) {
+ dst_prog, multi_func)) {
if (dst_prog)
bpf_prog_put(dst_prog);
if (attach_btf)
@@ -3042,7 +3060,7 @@ static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, struct bpf_log_at
prog->expected_attach_type = attr->expected_attach_type;
prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE);
prog->aux->attach_btf = attach_btf;
- prog->aux->attach_btf_id = attr->attach_btf_id;
+ prog->aux->attach_btf_id = multi_func ? bpf_multi_func_btf_id[0] : attr->attach_btf_id;
prog->aux->dst_prog = dst_prog;
prog->aux->dev_bound = !!attr->prog_ifindex;
prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
@@ -4436,6 +4454,8 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
case BPF_MODIFY_RETURN:
return BPF_PROG_TYPE_TRACING;
case BPF_LSM_MAC:
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 90c4cfd31b58..c0e7bf96edaf 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -182,7 +182,8 @@ bool bpf_prog_has_trampoline(const struct bpf_prog *prog)
switch (ptype) {
case BPF_PROG_TYPE_TRACING:
if (eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT ||
- eatype == BPF_MODIFY_RETURN || eatype == BPF_TRACE_FSESSION)
+ eatype == BPF_MODIFY_RETURN || eatype == BPF_TRACE_FSESSION ||
+ eatype == BPF_TRACE_FENTRY_MULTI || eatype == BPF_TRACE_FEXIT_MULTI)
return true;
return false;
case BPF_PROG_TYPE_LSM:
@@ -781,10 +782,12 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog)
{
switch (prog->expected_attach_type) {
case BPF_TRACE_FENTRY:
+ case BPF_TRACE_FENTRY_MULTI:
return BPF_TRAMP_FENTRY;
case BPF_MODIFY_RETURN:
return BPF_TRAMP_MODIFY_RETURN;
case BPF_TRACE_FEXIT:
+ case BPF_TRACE_FEXIT_MULTI:
return BPF_TRAMP_FEXIT;
case BPF_TRACE_FSESSION:
return BPF_TRAMP_FSESSION;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index c8d980fdd709..58450cb88beb 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -16456,6 +16456,8 @@ static bool return_retval_range(struct bpf_verifier_env *env, struct bpf_retval_
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
*range = retval_range(0, 0);
break;
case BPF_TRACE_RAW_TP:
@@ -18837,6 +18839,11 @@ static int check_attach_modify_return(unsigned long addr, const char *func_name)
#endif /* CONFIG_FUNCTION_ERROR_INJECTION */
+static bool is_tracing_multi_id(const struct bpf_prog *prog, u32 btf_id)
+{
+ return is_tracing_multi(prog->expected_attach_type) && bpf_multi_func_btf_id[0] == btf_id;
+}
+
int bpf_check_attach_target(struct bpf_verifier_log *log,
const struct bpf_prog *prog,
const struct bpf_prog *tgt_prog,
@@ -18959,6 +18966,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
prog_extension &&
(tgt_prog->expected_attach_type == BPF_TRACE_FENTRY ||
tgt_prog->expected_attach_type == BPF_TRACE_FEXIT ||
+ tgt_prog->expected_attach_type == BPF_TRACE_FENTRY_MULTI ||
+ tgt_prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI ||
tgt_prog->expected_attach_type == BPF_TRACE_FSESSION)) {
/* Program extensions can extend all program types
* except fentry/fexit. The reason is the following.
@@ -19065,6 +19074,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
if (prog->expected_attach_type == BPF_TRACE_FSESSION &&
!bpf_jit_supports_fsession()) {
bpf_log(log, "JIT does not support fsession\n");
@@ -19094,7 +19105,18 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
if (ret < 0)
return ret;
- if (tgt_prog) {
+ /*
+ * *.multi programs don't need an address during program
+ * verification, we just take the module ref if needed.
+ */
+ if (is_tracing_multi_id(prog, btf_id)) {
+ if (btf_is_module(btf)) {
+ mod = btf_try_get_module(btf);
+ if (!mod)
+ return -ENOENT;
+ }
+ addr = 0;
+ } else if (tgt_prog) {
if (subprog == 0)
addr = (long) tgt_prog->bpf_func;
else
@@ -19122,6 +19144,12 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
ret = -EINVAL;
switch (prog->type) {
case BPF_PROG_TYPE_TRACING:
+ /* *.multi sleepable programs will pass initial sleepable check,
+ * the actual attached btf ids are checked later during the link
+ * attachment.
+ */
+ if (is_tracing_multi_id(prog, btf_id))
+ ret = 0;
if (!check_attach_sleepable(btf_id, addr, tname))
ret = 0;
/* fentry/fexit/fmod_ret progs can also be sleepable if they are
@@ -19232,6 +19260,8 @@ static bool can_be_sleepable(struct bpf_prog *prog)
case BPF_TRACE_ITER:
case BPF_TRACE_FSESSION:
case BPF_TRACE_RAW_TP:
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
return true;
default:
return false;
@@ -19323,6 +19353,14 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return -EINVAL;
}
+ /*
+ * We don't get trampoline for tracing_multi programs at this point,
+ * it's done when tracing_multi link is created.
+ */
+ if (prog->type == BPF_PROG_TYPE_TRACING &&
+ is_tracing_multi(prog->expected_attach_type))
+ return 0;
+
key = bpf_trampoline_compute_key(tgt_prog, prog->aux->attach_btf, btf_id);
tr = bpf_trampoline_get(key, &tgt_info);
if (!tr)
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index c9aea7052ba7..67769c700cae 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -703,6 +703,8 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
if (bpf_fentry_test1(1) != 2 ||
bpf_fentry_test2(2, 3) != 5 ||
bpf_fentry_test3(4, 5, 6) != 15 ||
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 37142e6d911a..7b1a1552491e 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1155,6 +1155,8 @@ enum bpf_attach_type {
BPF_TRACE_KPROBE_SESSION,
BPF_TRACE_UPROBE_SESSION,
BPF_TRACE_FSESSION,
+ BPF_TRACE_FENTRY_MULTI,
+ BPF_TRACE_FEXIT_MULTI,
__MAX_BPF_ATTACH_TYPE
};
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index ab2071fdd3e8..bfed9b076a98 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -136,6 +136,8 @@ static const char * const attach_type_name[] = {
[BPF_NETKIT_PEER] = "netkit_peer",
[BPF_TRACE_KPROBE_SESSION] = "trace_kprobe_session",
[BPF_TRACE_UPROBE_SESSION] = "trace_uprobe_session",
+ [BPF_TRACE_FENTRY_MULTI] = "trace_fentry_multi",
+ [BPF_TRACE_FEXIT_MULTI] = "trace_fexit_multi",
};
static const char * const link_type_name[] = {
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* Re: [PATCHv6 bpf-next 10/29] bpf: Add multi tracing attach types
2026-05-27 11:39 ` [PATCHv6 bpf-next 10/29] bpf: Add multi tracing attach types Jiri Olsa
@ 2026-05-27 12:59 ` bot+bpf-ci
0 siblings, 0 replies; 34+ messages in thread
From: bot+bpf-ci @ 2026-05-27 12:59 UTC (permalink / raw)
To: jolsa, ast, daniel, andrii
Cc: bpf, linux-trace-kernel, kafai, eddyz87, songliubraving, yhs,
menglong8.dong, rostedt, ast, andrii, daniel, martin.lau, eddyz87,
yonghong.song, clm, ihor.solodrai
[-- Attachment #1: Type: text/plain, Size: 4405 bytes --]
> diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
> index 435ae6efe961..27ad0c265c95 100644
> --- a/kernel/bpf/syscall.c
> +++ b/kernel/bpf/syscall.c
> @@ -41,6 +41,7 @@
> #include <linux/overflow.h>
> #include <linux/cookie.h>
> #include <linux/verification.h>
> +#include <linux/btf_ids.h>
>
> #include <net/netfilter/nf_bpf_link.h>
> #include <net/netkit.h>
[ ... ]
> @@ -2904,6 +2914,11 @@ static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog)
> return 0;
> }
>
> +extern int bpf_multi_func(void);
> +int __init __used bpf_multi_func(void) { return 0; }
The signature change from v5 to v6 creates a potential issue. In v5,
bpf_multi_func had 6 arguments (matching the initial verifier setup):
int __init __used bpf_multi_func(u64 r1, u64 r2, u64 r3,
u64 r4, u64 r5, u64 r6)
Now it has no arguments. The Sashiko AI review in v5 identified that
context array bounds checking could fail when bpf_multi_func's argument
count doesn't match the attached function's argument count, and the
author acknowledged the need to disable direct context access.
Since the initial verification happens against bpf_multi_func (which now
has 0 arguments), but the verifier previously allowed direct ctx[0-5]
accesses based on the 6-argument version, is there still a path where
direct context accesses could be allowed? If so, would accessing ctx[0]
on a function with 0 arguments lead to out-of-bounds kernel stack reads?
The earlier review suggested either:
(a) explicitly disabling direct memory accesses to the ctx array for
FENTRY_MULTI and FEXIT_MULTI, or
(b) enforcing the use of bounds-checked helpers like bpf_get_func_arg()
Was this implemented somewhere in the patch series?
> +
> +BTF_ID_LIST_GLOBAL_SINGLE(bpf_multi_func_btf_id, func, bpf_multi_func)
[ ... ]
> diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
> index c8d980fdd709..58450cb88beb 100644
> --- a/kernel/bpf/verifier.c
> +++ b/kernel/bpf/verifier.c
[ ... ]
> @@ -18837,6 +18839,11 @@ static int check_attach_modify_return(unsigned long addr, const char *func_name)
>
> #endif /* CONFIG_FUNCTION_ERROR_INJECTION */
>
> +static bool is_tracing_multi_id(const struct bpf_prog *prog, u32 btf_id)
> +{
> + return is_tracing_multi(prog->expected_attach_type) && bpf_multi_func_btf_id[0] == btf_id;
> +}
> +
> int bpf_check_attach_target(struct bpf_verifier_log *log,
> const struct bpf_prog *prog,
> const struct bpf_prog *tgt_prog,
[ ... ]
> @@ -19094,7 +19105,18 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
> if (ret < 0)
> return ret;
>
> - if (tgt_prog) {
> + /*
> + * *.multi programs don't need an address during program
> + * verification, we just take the module ref if needed.
> + */
> + if (is_tracing_multi_id(prog, btf_id)) {
> + if (btf_is_module(btf)) {
> + mod = btf_try_get_module(btf);
> + if (!mod)
> + return -ENOENT;
> + }
> + addr = 0;
> + } else if (tgt_prog) {
> if (subprog == 0)
> addr = (long) tgt_prog->bpf_func;
> else
[ ... ]
> @@ -19122,6 +19144,12 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
> ret = -EINVAL;
> switch (prog->type) {
> case BPF_PROG_TYPE_TRACING:
> + /* *.multi sleepable programs will pass initial sleepable check,
> + * the actual attached btf ids are checked later during the link
> + * attachment.
> + */
> + if (is_tracing_multi_id(prog, btf_id))
> + ret = 0;
> if (!check_attach_sleepable(btf_id, addr, tname))
> ret = 0;
The multi types are not included in btf_validate_prog_ctx_type() in
kernel/bpf/btf.c. That function validates which attach types allow u64*
as their ctx parameter:
kernel/bpf/btf.c:btf_validate_prog_ctx_type() {
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_MODIFY_RETURN:
...
}
Since BPF_TRACE_FENTRY_MULTI and BPF_TRACE_FEXIT_MULTI also use u64*
context, do they need to be added to that validation list? Or if direct
context access should be disabled for multi types (per the earlier
review concern), should they be handled with special rejection logic?
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26509800686
^ permalink raw reply [flat|nested] 34+ messages in thread
* [PATCHv6 bpf-next 11/29] bpf: Move sleepable verification code to btf_id_allow_sleepable
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (9 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 10/29] bpf: Add multi tracing attach types Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 12/29] bpf: Add bpf_trampoline_multi_attach/detach functions Jiri Olsa
` (17 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Move sleepable verification code to btf_id_allow_sleepable function.
It will be used in following changes.
Adding code to retrieve type's name instead of passing it from
bpf_check_attach_target function, because this function will be
called from another place in following changes and it's easier
to retrieve the name directly in here.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/bpf/verifier.c | 82 ++++++++++++++++++++++++++-----------------
1 file changed, 50 insertions(+), 32 deletions(-)
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 58450cb88beb..9eb0ebd0f93c 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -18844,6 +18844,55 @@ static bool is_tracing_multi_id(const struct bpf_prog *prog, u32 btf_id)
return is_tracing_multi(prog->expected_attach_type) && bpf_multi_func_btf_id[0] == btf_id;
}
+static int btf_id_allow_sleepable(u32 btf_id, unsigned long addr, const struct bpf_prog *prog,
+ const struct btf *btf)
+{
+ const struct btf_type *t;
+ const char *tname;
+
+ switch (prog->type) {
+ case BPF_PROG_TYPE_TRACING:
+ t = btf_type_by_id(btf, btf_id);
+ if (!t)
+ return -EINVAL;
+ tname = btf_name_by_offset(btf, t->name_off);
+ if (!tname)
+ return -EINVAL;
+
+ /*
+ * *.multi sleepable programs will pass initial sleepable check,
+ * the actual attached btf ids are checked later during the link
+ * attachment.
+ */
+ if (is_tracing_multi_id(prog, btf_id))
+ return 0;
+ if (!check_attach_sleepable(btf_id, addr, tname))
+ return 0;
+ /*
+ * fentry/fexit/fmod_ret progs can also be sleepable if they are
+ * in the fmodret id set with the KF_SLEEPABLE flag.
+ */
+ else {
+ u32 *flags = btf_kfunc_is_modify_return(btf, btf_id, prog);
+
+ if (flags && (*flags & KF_SLEEPABLE))
+ return 0;
+ }
+ break;
+ case BPF_PROG_TYPE_LSM:
+ /*
+ * LSM progs check that they are attached to bpf_lsm_*() funcs.
+ * Only some of them are sleepable.
+ */
+ if (bpf_lsm_is_sleepable_hook(btf_id))
+ return 0;
+ break;
+ default:
+ break;
+ }
+ return -EINVAL;
+}
+
int bpf_check_attach_target(struct bpf_verifier_log *log,
const struct bpf_prog *prog,
const struct bpf_prog *tgt_prog,
@@ -19141,38 +19190,7 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
}
if (prog->sleepable) {
- ret = -EINVAL;
- switch (prog->type) {
- case BPF_PROG_TYPE_TRACING:
- /* *.multi sleepable programs will pass initial sleepable check,
- * the actual attached btf ids are checked later during the link
- * attachment.
- */
- if (is_tracing_multi_id(prog, btf_id))
- ret = 0;
- if (!check_attach_sleepable(btf_id, addr, tname))
- ret = 0;
- /* fentry/fexit/fmod_ret progs can also be sleepable if they are
- * in the fmodret id set with the KF_SLEEPABLE flag.
- */
- else {
- u32 *flags = btf_kfunc_is_modify_return(btf, btf_id,
- prog);
-
- if (flags && (*flags & KF_SLEEPABLE))
- ret = 0;
- }
- break;
- case BPF_PROG_TYPE_LSM:
- /* LSM progs check that they are attached to bpf_lsm_*() funcs.
- * Only some of them are sleepable.
- */
- if (bpf_lsm_is_sleepable_hook(btf_id))
- ret = 0;
- break;
- default:
- break;
- }
+ ret = btf_id_allow_sleepable(btf_id, addr, prog, btf);
if (ret) {
module_put(mod);
bpf_log(log, "%s is not sleepable\n", tname);
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 12/29] bpf: Add bpf_trampoline_multi_attach/detach functions
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (10 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 11/29] bpf: Move sleepable verification code to btf_id_allow_sleepable Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 13/29] bpf: Add support for tracing multi link Jiri Olsa
` (16 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding bpf_trampoline_multi_attach/detach functions that allows to
attach/detach tracing program to multiple functions/trampolines.
The attachment is defined with bpf_program and array of BTF ids of
functions to attach the bpf program to.
Adding bpf_tracing_multi_link object that holds all the attached
trampolines and is initialized in attach and used in detach.
The attachment allocates or uses currently existing trampoline
for each function to attach and links it with the bpf program.
The attach works as follows:
- we get all the needed trampolines
- lock them and add the bpf program to each (__bpf_trampoline_link_prog)
- the trampoline_multi_ops passed in __bpf_trampoline_link_prog gathers
ftrace_hash (ip -> trampoline) objects
- we call update_ftrace_direct_add/mod to update needed locations
- we unlock all the trampolines
The detach works as follows:
- we lock all the needed trampolines
- remove the program from each (__bpf_trampoline_unlink_prog)
- the trampoline_multi_ops passed in __bpf_trampoline_unlink_prog gathers
ftrace_hash (ip -> trampoline) objects
- we call update_ftrace_direct_del/mod to update needed locations
- we unlock and put all the trampolines
We store the old image/flags in the trampoline before the update
and use it in case we need to rollback the attachment.
We keep the ftrace_hash objects allocated during attach in the link
so they can be used for detach as well.
Adding trampoline_(un)lock_all functions to (un)lock all trampolines
to gate the tracing_multi attachment.
Note this is supported only for archs (x86_64) with ftrace direct and
have single ops support.
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS &&
CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS
It also needs CONFIG_BPF_SYSCALL enabled.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 43 ++++++
include/linux/bpf_verifier.h | 4 +
kernel/bpf/trampoline.c | 271 +++++++++++++++++++++++++++++++++++
kernel/bpf/verifier.c | 52 +++++++
4 files changed, 370 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index adae0674d329..93a94669ca90 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -32,6 +32,7 @@
#include <linux/static_call.h>
#include <linux/memcontrol.h>
#include <linux/cfi.h>
+#include <linux/ftrace.h>
#include <asm/rqspinlock.h>
struct bpf_verifier_env;
@@ -1371,6 +1372,11 @@ struct bpf_trampoline {
int progs_cnt[BPF_TRAMP_MAX];
/* Executable image of trampoline */
struct bpf_tramp_image *cur_image;
+ /* Used as temporary old image storage for multi_attach */
+ struct {
+ struct bpf_tramp_image *old_image;
+ u32 old_flags;
+ } multi_attach;
};
struct bpf_attach_target_info {
@@ -1468,6 +1474,8 @@ static inline int bpf_dynptr_check_off_len(const struct bpf_dynptr_kern *ptr, u6
return 0;
}
+struct bpf_tracing_multi_link;
+
#ifdef CONFIG_BPF_JIT
int bpf_trampoline_link_prog(struct bpf_tramp_node *node,
struct bpf_trampoline *tr,
@@ -1480,6 +1488,11 @@ struct bpf_trampoline *bpf_trampoline_get(u64 key,
void bpf_trampoline_put(struct bpf_trampoline *tr);
int arch_prepare_bpf_dispatcher(void *image, void *buf, s64 *funcs, int num_funcs);
+int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids,
+ struct bpf_tracing_multi_link *link);
+int bpf_trampoline_multi_detach(struct bpf_prog *prog,
+ struct bpf_tracing_multi_link *link);
+
/*
* When the architecture supports STATIC_CALL replace the bpf_dispatcher_fn
* indirection with a direct call to the bpf program. If the architecture does
@@ -1592,6 +1605,16 @@ static inline bool bpf_prog_has_trampoline(const struct bpf_prog *prog)
{
return false;
}
+static inline int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids,
+ struct bpf_tracing_multi_link *link)
+{
+ return -ENOTSUPP;
+}
+static inline int bpf_trampoline_multi_detach(struct bpf_prog *prog,
+ struct bpf_tracing_multi_link *link)
+{
+ return -ENOTSUPP;
+}
#endif
struct bpf_func_info_aux {
@@ -1912,6 +1935,26 @@ struct bpf_tracing_link {
struct bpf_prog *tgt_prog;
};
+struct bpf_tracing_multi_node {
+ struct bpf_tramp_node node;
+ struct bpf_trampoline *trampoline;
+ struct ftrace_func_entry entry;
+};
+
+struct bpf_tracing_multi_data {
+ struct ftrace_hash *unreg;
+ struct ftrace_hash *modify;
+ struct ftrace_hash *reg;
+ struct ftrace_func_entry *entry;
+};
+
+struct bpf_tracing_multi_link {
+ struct bpf_link link;
+ struct bpf_tracing_multi_data data;
+ int nodes_cnt;
+ struct bpf_tracing_multi_node nodes[] __counted_by(nodes_cnt);
+};
+
struct bpf_raw_tp_link {
struct bpf_link link;
struct bpf_raw_event_map *btp;
diff --git a/include/linux/bpf_verifier.h b/include/linux/bpf_verifier.h
index 5cbad3b64130..ecb85bd58295 100644
--- a/include/linux/bpf_verifier.h
+++ b/include/linux/bpf_verifier.h
@@ -1596,6 +1596,10 @@ int bpf_add_kfunc_call(struct bpf_verifier_env *env, u32 func_id, u16 offset);
int bpf_fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
struct bpf_insn *insn_buf, int insn_idx, int *cnt);
+/* Functions exported from verifier.c, used by trampoline.c */
+int bpf_check_attach_btf_id_multi(struct btf *btf, struct bpf_prog *prog, u32 btf_id,
+ struct bpf_attach_target_info *tgt_info);
+
/* Functions in fixups.c, called from bpf_check() */
int bpf_remove_fastcall_spills_fills(struct bpf_verifier_env *env);
int bpf_optimize_bpf_loop(struct bpf_verifier_env *env);
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index c0e7bf96edaf..476b7db3a809 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -1447,6 +1447,277 @@ int __weak arch_bpf_trampoline_size(const struct btf_func_model *m, u32 flags,
return -ENOTSUPP;
}
+#if defined(CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS) && \
+ defined(CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS) && \
+ defined(CONFIG_BPF_SYSCALL)
+
+static void trampoline_lock_all(void)
+{
+ int i;
+
+ for (i = 0; i < TRAMPOLINE_LOCKS_TABLE_SIZE; i++)
+ mutex_lock(&trampoline_locks[i].mutex);
+}
+
+static void trampoline_unlock_all(void)
+{
+ int i;
+
+ for (i = 0; i < TRAMPOLINE_LOCKS_TABLE_SIZE; i++)
+ mutex_unlock(&trampoline_locks[i].mutex);
+}
+
+static void remove_tracing_multi_data(struct bpf_tracing_multi_data *data)
+{
+ ftrace_hash_remove(data->reg);
+ ftrace_hash_remove(data->unreg);
+ ftrace_hash_remove(data->modify);
+}
+
+static void clear_tracing_multi_data(struct bpf_tracing_multi_data *data)
+{
+ remove_tracing_multi_data(data);
+
+ free_ftrace_hash(data->reg);
+ free_ftrace_hash(data->unreg);
+ free_ftrace_hash(data->modify);
+}
+
+static int init_tracing_multi_data(struct bpf_tracing_multi_data *data)
+{
+ data->reg = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
+ data->unreg = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
+ data->modify = alloc_ftrace_hash(FTRACE_HASH_DEFAULT_BITS);
+
+ if (!data->reg || !data->unreg || !data->modify) {
+ clear_tracing_multi_data(data);
+ return -ENOMEM;
+ }
+ return 0;
+}
+
+static void ftrace_hash_add(struct ftrace_hash *hash, struct ftrace_func_entry *entry,
+ unsigned long ip, unsigned long direct)
+{
+ entry->ip = ip;
+ entry->direct = direct;
+ add_ftrace_hash_entry(hash, entry);
+}
+
+static int register_fentry_multi(struct bpf_trampoline *tr, struct bpf_tramp_image *im, void *ptr)
+{
+ unsigned long addr = (unsigned long) im->image;
+ unsigned long ip = ftrace_location(tr->ip);
+ struct bpf_tracing_multi_data *data = ptr;
+
+ if (bpf_trampoline_use_jmp(tr->flags))
+ addr = ftrace_jmp_set(addr);
+
+ ftrace_hash_add(data->reg, data->entry, ip, addr);
+ tr->cur_image = im;
+ return 0;
+}
+
+static int unregister_fentry_multi(struct bpf_trampoline *tr, u32 orig_flags, void *ptr)
+{
+ unsigned long addr = (unsigned long) tr->cur_image->image;
+ unsigned long ip = ftrace_location(tr->ip);
+ struct bpf_tracing_multi_data *data = ptr;
+
+ if (bpf_trampoline_use_jmp(tr->flags))
+ addr = ftrace_jmp_set(addr);
+
+ ftrace_hash_add(data->unreg, data->entry, ip, addr);
+ tr->cur_image = NULL;
+ return 0;
+}
+
+static int modify_fentry_multi(struct bpf_trampoline *tr, u32 orig_flags, struct bpf_tramp_image *im,
+ bool lock_direct_mutex, void *ptr)
+{
+ unsigned long addr = (unsigned long) im->image;
+ unsigned long ip = ftrace_location(tr->ip);
+ struct bpf_tracing_multi_data *data = ptr;
+
+ if (bpf_trampoline_use_jmp(tr->flags))
+ addr = ftrace_jmp_set(addr);
+
+ ftrace_hash_add(data->modify, data->entry, ip, addr);
+ tr->cur_image = im;
+ return 0;
+}
+
+static const struct bpf_trampoline_ops trampoline_multi_ops = {
+ .register_fentry = register_fentry_multi,
+ .unregister_fentry = unregister_fentry_multi,
+ .modify_fentry = modify_fentry_multi,
+};
+
+static void bpf_trampoline_multi_attach_init(struct bpf_trampoline *tr)
+{
+ tr->multi_attach.old_image = tr->cur_image;
+ tr->multi_attach.old_flags = tr->flags;
+}
+
+static void bpf_trampoline_multi_attach_free(struct bpf_trampoline *tr)
+{
+ if (tr->multi_attach.old_image)
+ bpf_tramp_image_put(tr->multi_attach.old_image);
+
+ tr->multi_attach.old_image = NULL;
+ tr->multi_attach.old_flags = 0;
+}
+
+static void bpf_trampoline_multi_attach_rollback(struct bpf_trampoline *tr)
+{
+ if (tr->cur_image)
+ bpf_tramp_image_put(tr->cur_image);
+ tr->cur_image = tr->multi_attach.old_image;
+ tr->flags = tr->multi_attach.old_flags;
+
+ tr->multi_attach.old_image = NULL;
+ tr->multi_attach.old_flags = 0;
+}
+
+#define for_each_mnode_cnt(mnode, link, cnt) \
+ for (i = 0, mnode = &link->nodes[i]; i < cnt; i++, mnode = &link->nodes[i])
+
+#define for_each_mnode(mnode, link) \
+ for_each_mnode_cnt(mnode, link, link->nodes_cnt)
+
+int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids,
+ struct bpf_tracing_multi_link *link)
+{
+ struct bpf_tracing_multi_data *data = &link->data;
+ struct bpf_attach_target_info tgt_info = {};
+ struct btf *btf = prog->aux->attach_btf;
+ struct bpf_tracing_multi_node *mnode;
+ struct bpf_trampoline *tr;
+ int i, err, rollback_cnt;
+ u64 key;
+
+ for_each_mnode(mnode, link) {
+ rollback_cnt = i;
+
+ err = bpf_check_attach_btf_id_multi(btf, prog, ids[i], &tgt_info);
+ if (err)
+ goto rollback_put;
+
+ key = bpf_trampoline_compute_key(NULL, btf, ids[i]);
+
+ tr = bpf_trampoline_get(key, &tgt_info);
+ if (!tr) {
+ err = -ENOMEM;
+ goto rollback_put;
+ }
+
+ mnode->trampoline = tr;
+ mnode->node.link = &link->link;
+
+ cond_resched();
+ }
+
+ err = init_tracing_multi_data(data);
+ if (err) {
+ rollback_cnt = link->nodes_cnt;
+ goto rollback_put;
+ }
+
+ trampoline_lock_all();
+
+ for_each_mnode(mnode, link) {
+ bpf_trampoline_multi_attach_init(mnode->trampoline);
+
+ data->entry = &mnode->entry;
+ err = __bpf_trampoline_link_prog(&mnode->node, mnode->trampoline, NULL,
+ &trampoline_multi_ops, data);
+ if (err) {
+ rollback_cnt = i;
+ goto rollback_unlink;
+ }
+ }
+
+ rollback_cnt = link->nodes_cnt;
+ if (ftrace_hash_count(data->reg)) {
+ err = update_ftrace_direct_add(&direct_ops, data->reg);
+ if (err)
+ goto rollback_unlink;
+ }
+
+ if (ftrace_hash_count(data->modify)) {
+ err = update_ftrace_direct_mod(&direct_ops, data->modify, true);
+ if (err) {
+ if (ftrace_hash_count(data->reg))
+ WARN_ON_ONCE(update_ftrace_direct_del(&direct_ops, data->reg));
+ goto rollback_unlink;
+ }
+ }
+
+ for_each_mnode(mnode, link)
+ bpf_trampoline_multi_attach_free(mnode->trampoline);
+
+ trampoline_unlock_all();
+
+ remove_tracing_multi_data(data);
+ return 0;
+
+rollback_unlink:
+ for_each_mnode_cnt(mnode, link, rollback_cnt) {
+ bpf_trampoline_remove_prog(mnode->trampoline, &mnode->node);
+ bpf_trampoline_multi_attach_rollback(mnode->trampoline);
+ }
+
+ trampoline_unlock_all();
+
+ clear_tracing_multi_data(data);
+ rollback_cnt = link->nodes_cnt;
+
+rollback_put:
+ for_each_mnode_cnt(mnode, link, rollback_cnt)
+ bpf_trampoline_put(mnode->trampoline);
+
+ return err;
+}
+
+int bpf_trampoline_multi_detach(struct bpf_prog *prog, struct bpf_tracing_multi_link *link)
+{
+ struct bpf_tracing_multi_data *data = &link->data;
+ struct bpf_tracing_multi_node *mnode;
+ int i;
+
+ trampoline_lock_all();
+
+ for_each_mnode(mnode, link) {
+ data->entry = &mnode->entry;
+ bpf_trampoline_multi_attach_init(mnode->trampoline);
+ WARN_ON_ONCE(__bpf_trampoline_unlink_prog(&mnode->node, mnode->trampoline,
+ NULL, &trampoline_multi_ops, data));
+ }
+
+ if (ftrace_hash_count(data->unreg))
+ WARN_ON_ONCE(update_ftrace_direct_del(&direct_ops, data->unreg));
+ if (ftrace_hash_count(data->modify))
+ WARN_ON_ONCE(update_ftrace_direct_mod(&direct_ops, data->modify, true));
+
+ for_each_mnode(mnode, link)
+ bpf_trampoline_multi_attach_free(mnode->trampoline);
+
+ trampoline_unlock_all();
+
+ for_each_mnode(mnode, link)
+ bpf_trampoline_put(mnode->trampoline);
+
+ clear_tracing_multi_data(data);
+ return 0;
+}
+
+#undef for_each_mnode_cnt
+#undef for_each_mnode
+
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS &&
+ CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS &&
+ CONFIG_BPF_SYSCALL */
+
static int __init init_trampolines(void)
{
int i;
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index 9eb0ebd0f93c..dca756034458 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -19391,6 +19391,58 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return 0;
}
+int bpf_check_attach_btf_id_multi(struct btf *btf, struct bpf_prog *prog, u32 btf_id,
+ struct bpf_attach_target_info *tgt_info)
+{
+ const struct btf_type *t;
+ unsigned long addr;
+ const char *tname;
+ int err;
+
+ if (!btf_id || !btf)
+ return -EINVAL;
+
+ /* Check noreturn attachment. */
+ if (prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI &&
+ btf_id_set_contains(&noreturn_deny, btf_id))
+ return -EINVAL;
+
+ /* Check and get function target data. */
+ t = btf_type_by_id(btf, btf_id);
+ if (!t)
+ return -EINVAL;
+ tname = btf_name_by_offset(btf, t->name_off);
+ if (!tname)
+ return -EINVAL;
+ if (!btf_type_is_func(t))
+ return -EINVAL;
+ t = btf_type_by_id(btf, t->type);
+ if (!btf_type_is_func_proto(t))
+ return -EINVAL;
+ err = btf_distill_func_proto(NULL, btf, t, tname, &tgt_info->fmodel);
+ if (err < 0)
+ return err;
+ if (btf_is_module(btf)) {
+ /* The bpf program already holds reference to module. */
+ if (WARN_ON_ONCE(!prog->aux->mod))
+ return -EINVAL;
+ addr = find_kallsyms_symbol_value(prog->aux->mod, tname);
+ } else {
+ addr = kallsyms_lookup_name(tname);
+ }
+ if (!addr || !ftrace_location(addr))
+ return -ENOENT;
+
+ /* Check sleepable program attachment. */
+ if (prog->sleepable) {
+ err = btf_id_allow_sleepable(btf_id, addr, prog, btf);
+ if (err)
+ return err;
+ }
+ tgt_info->tgt_addr = addr;
+ return 0;
+}
+
struct btf *bpf_get_btf_vmlinux(void)
{
if (!btf_vmlinux && IS_ENABLED(CONFIG_DEBUG_INFO_BTF)) {
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 13/29] bpf: Add support for tracing multi link
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (11 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 12/29] bpf: Add bpf_trampoline_multi_attach/detach functions Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 14/29] bpf: Add support for tracing_multi link cookies Jiri Olsa
` (15 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding new link to allow to attach program to multiple function
BTF IDs. The link is represented by struct bpf_tracing_multi_link.
To configure the link, new fields are added to bpf_attr::link_create
to pass array of BTF IDs;
struct {
__aligned_u64 ids;
__u32 cnt;
} tracing_multi;
Each BTF ID represents function (BTF_KIND_FUNC) that the link will
attach bpf program to.
We use previously added bpf_trampoline_multi_attach/detach functions
to attach/detach the link.
The linkinfo/fdinfo callbacks will be implemented in following changes.
Note this is supported only for archs (x86_64) with ftrace direct and
have single ops support.
CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS &&
CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf_types.h | 1 +
include/linux/trace_events.h | 6 ++
include/uapi/linux/bpf.h | 5 ++
kernel/bpf/syscall.c | 2 +
kernel/trace/bpf_trace.c | 123 +++++++++++++++++++++++++++++++++
tools/include/uapi/linux/bpf.h | 6 ++
tools/lib/bpf/libbpf.c | 1 +
7 files changed, 144 insertions(+)
diff --git a/include/linux/bpf_types.h b/include/linux/bpf_types.h
index b13de31e163f..96575b5b563e 100644
--- a/include/linux/bpf_types.h
+++ b/include/linux/bpf_types.h
@@ -155,3 +155,4 @@ BPF_LINK_TYPE(BPF_LINK_TYPE_PERF_EVENT, perf)
BPF_LINK_TYPE(BPF_LINK_TYPE_KPROBE_MULTI, kprobe_multi)
BPF_LINK_TYPE(BPF_LINK_TYPE_STRUCT_OPS, struct_ops)
BPF_LINK_TYPE(BPF_LINK_TYPE_UPROBE_MULTI, uprobe_multi)
+BPF_LINK_TYPE(BPF_LINK_TYPE_TRACING_MULTI, tracing_multi)
diff --git a/include/linux/trace_events.h b/include/linux/trace_events.h
index d49338c44014..308c76b57d13 100644
--- a/include/linux/trace_events.h
+++ b/include/linux/trace_events.h
@@ -787,6 +787,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id,
unsigned long *missed);
int bpf_kprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
int bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
+int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr);
#else
static inline unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx)
{
@@ -844,6 +845,11 @@ bpf_uprobe_multi_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
{
return -EOPNOTSUPP;
}
+static inline int
+bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
+{
+ return -EOPNOTSUPP;
+}
#endif
enum {
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 0cde0e2f3d4b..951a0122baaf 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1181,6 +1181,7 @@ enum bpf_link_type {
BPF_LINK_TYPE_UPROBE_MULTI = 12,
BPF_LINK_TYPE_NETKIT = 13,
BPF_LINK_TYPE_SOCKMAP = 14,
+ BPF_LINK_TYPE_TRACING_MULTI = 15,
__MAX_BPF_LINK_TYPE,
};
@@ -1871,6 +1872,10 @@ union bpf_attr {
};
__u64 expected_revision;
} cgroup;
+ struct {
+ __aligned_u64 ids;
+ __u32 cnt;
+ } tracing_multi;
};
} link_create;
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 27ad0c265c95..8fcdcb3c4eab 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -5841,6 +5841,8 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr)
ret = bpf_iter_link_attach(attr, uattr, prog);
else if (prog->expected_attach_type == BPF_LSM_CGROUP)
ret = cgroup_bpf_link_attach(attr, prog);
+ else if (is_tracing_multi(prog->expected_attach_type))
+ ret = bpf_tracing_multi_attach(prog, attr);
else
ret = bpf_tracing_prog_attach(prog,
attr->link_create.target_fd,
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index d853f97bd154..7cf22d69a1e1 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -42,6 +42,7 @@
#define MAX_UPROBE_MULTI_CNT (1U << 20)
#define MAX_KPROBE_MULTI_CNT (1U << 20)
+#define MAX_TRACING_MULTI_CNT (1U << 20)
#ifdef CONFIG_MODULES
struct bpf_trace_module {
@@ -3641,3 +3642,125 @@ __bpf_kfunc int bpf_copy_from_user_task_str_dynptr(const struct bpf_dynptr *dptr
}
__bpf_kfunc_end_defs();
+
+#if defined(CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS) && \
+ defined(CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS)
+
+static void bpf_tracing_multi_link_release(struct bpf_link *link)
+{
+ struct bpf_tracing_multi_link *tr_link =
+ container_of(link, struct bpf_tracing_multi_link, link);
+
+ WARN_ON_ONCE(bpf_trampoline_multi_detach(link->prog, tr_link));
+}
+
+static void bpf_tracing_multi_link_dealloc(struct bpf_link *link)
+{
+ struct bpf_tracing_multi_link *tr_link =
+ container_of(link, struct bpf_tracing_multi_link, link);
+
+ kvfree(tr_link);
+}
+
+static const struct bpf_link_ops bpf_tracing_multi_link_lops = {
+ .release = bpf_tracing_multi_link_release,
+ .dealloc_deferred = bpf_tracing_multi_link_dealloc,
+};
+
+static int ids_cmp(const void *pa, const void *pb)
+{
+ u32 a = *(u32 *) pa;
+ u32 b = *(u32 *) pb;
+
+ return (a > b) - (a < b);
+}
+
+static int check_dup_ids(u32 *ids, u32 cnt)
+{
+ u32 *sorted;
+ int err = 0;
+
+ sorted = kmemdup(ids, cnt * sizeof(*ids), GFP_KERNEL);
+ if (!sorted)
+ return -ENOMEM;
+
+ sort(sorted, cnt, sizeof(sorted[0]), ids_cmp, NULL);
+ for (int i = 1; i < cnt; i++) {
+ if (sorted[i] == sorted[i - 1]) {
+ err = -EINVAL;
+ break;
+ }
+ }
+
+ kfree(sorted);
+ return err;
+}
+
+int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
+{
+ struct bpf_tracing_multi_link *link = NULL;
+ struct bpf_link_primer link_primer;
+ u32 cnt, *ids = NULL;
+ u32 __user *uids;
+ int err;
+
+ uids = u64_to_user_ptr(attr->link_create.tracing_multi.ids);
+ cnt = attr->link_create.tracing_multi.cnt;
+
+ if (!cnt || !uids)
+ return -EINVAL;
+ if (cnt > MAX_TRACING_MULTI_CNT)
+ return -E2BIG;
+ if (attr->link_create.flags || attr->link_create.target_fd)
+ return -EINVAL;
+
+ ids = kvmalloc_objs(*ids, cnt);
+ if (!ids)
+ return -ENOMEM;
+
+ if (copy_from_user(ids, uids, cnt * sizeof(*ids))) {
+ err = -EFAULT;
+ goto error;
+ }
+
+ err = check_dup_ids(ids, cnt);
+ if (err)
+ goto error;
+
+ link = kvzalloc_flex(*link, nodes, cnt);
+ if (!link) {
+ err = -ENOMEM;
+ goto error;
+ }
+
+ bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING_MULTI,
+ &bpf_tracing_multi_link_lops, prog, prog->expected_attach_type);
+
+ err = bpf_link_prime(&link->link, &link_primer);
+ if (err)
+ goto error;
+
+ link->nodes_cnt = cnt;
+
+ err = bpf_trampoline_multi_attach(prog, ids, link);
+ kvfree(ids);
+ if (err) {
+ bpf_link_cleanup(&link_primer);
+ return err;
+ }
+ return bpf_link_settle(&link_primer);
+
+error:
+ kvfree(ids);
+ kvfree(link);
+ return err;
+}
+
+#else
+
+int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
+{
+ return -EOPNOTSUPP;
+}
+
+#endif /* CONFIG_DYNAMIC_FTRACE_WITH_DIRECT_CALLS && CONFIG_HAVE_SINGLE_FTRACE_DIRECT_OPS */
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 7b1a1552491e..951a0122baaf 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1181,6 +1181,7 @@ enum bpf_link_type {
BPF_LINK_TYPE_UPROBE_MULTI = 12,
BPF_LINK_TYPE_NETKIT = 13,
BPF_LINK_TYPE_SOCKMAP = 14,
+ BPF_LINK_TYPE_TRACING_MULTI = 15,
__MAX_BPF_LINK_TYPE,
};
@@ -1871,6 +1872,10 @@ union bpf_attr {
};
__u64 expected_revision;
} cgroup;
+ struct {
+ __aligned_u64 ids;
+ __u32 cnt;
+ } tracing_multi;
};
} link_create;
@@ -7246,6 +7251,7 @@ enum {
TCP_BPF_SOCK_OPS_CB_FLAGS = 1008, /* Get or Set TCP sock ops flags */
SK_BPF_CB_FLAGS = 1009, /* Get or set sock ops flags in socket */
SK_BPF_BYPASS_PROT_MEM = 1010, /* Get or Set sk->sk_bypass_prot_mem */
+
};
enum {
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index bfed9b076a98..7b99737590d1 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -156,6 +156,7 @@ static const char * const link_type_name[] = {
[BPF_LINK_TYPE_UPROBE_MULTI] = "uprobe_multi",
[BPF_LINK_TYPE_NETKIT] = "netkit",
[BPF_LINK_TYPE_SOCKMAP] = "sockmap",
+ [BPF_LINK_TYPE_TRACING_MULTI] = "tracing_multi",
};
static const char * const map_type_name[] = {
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 14/29] bpf: Add support for tracing_multi link cookies
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (12 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 13/29] bpf: Add support for tracing multi link Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 15/29] bpf: Add support for tracing_multi link session Jiri Olsa
` (14 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Add support to specify cookies for tracing_multi link.
Cookies are provided in array where each value is paired with provided
BTF ID value with the same array index.
Such cookie can be retrieved by bpf program with bpf_get_attach_cookie
helper call.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 1 +
include/uapi/linux/bpf.h | 1 +
kernel/bpf/trampoline.c | 1 +
kernel/trace/bpf_trace.c | 18 ++++++++++++++++++
tools/include/uapi/linux/bpf.h | 1 +
5 files changed, 22 insertions(+)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 93a94669ca90..03d4ce0ef93e 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1951,6 +1951,7 @@ struct bpf_tracing_multi_data {
struct bpf_tracing_multi_link {
struct bpf_link link;
struct bpf_tracing_multi_data data;
+ u64 *cookies;
int nodes_cnt;
struct bpf_tracing_multi_node nodes[] __counted_by(nodes_cnt);
};
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 951a0122baaf..39407a77133b 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1874,6 +1874,7 @@ union bpf_attr {
} cgroup;
struct {
__aligned_u64 ids;
+ __aligned_u64 cookies;
__u32 cnt;
} tracing_multi;
};
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index 476b7db3a809..acccf52f6792 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -1613,6 +1613,7 @@ int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids,
mnode->trampoline = tr;
mnode->node.link = &link->link;
+ mnode->node.cookie = link->cookies ? link->cookies[i] : 0;
cond_resched();
}
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 7cf22d69a1e1..6639751fab08 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3659,6 +3659,7 @@ static void bpf_tracing_multi_link_dealloc(struct bpf_link *link)
struct bpf_tracing_multi_link *tr_link =
container_of(link, struct bpf_tracing_multi_link, link);
+ kvfree(tr_link->cookies);
kvfree(tr_link);
}
@@ -3701,6 +3702,8 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
struct bpf_tracing_multi_link *link = NULL;
struct bpf_link_primer link_primer;
u32 cnt, *ids = NULL;
+ u64 __user *ucookies;
+ u64 *cookies = NULL;
u32 __user *uids;
int err;
@@ -3727,6 +3730,19 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
if (err)
goto error;
+ ucookies = u64_to_user_ptr(attr->link_create.tracing_multi.cookies);
+ if (ucookies) {
+ cookies = kvmalloc_objs(*cookies, cnt);
+ if (!cookies) {
+ err = -ENOMEM;
+ goto error;
+ }
+ if (copy_from_user(cookies, ucookies, cnt * sizeof(*cookies))) {
+ err = -EFAULT;
+ goto error;
+ }
+ }
+
link = kvzalloc_flex(*link, nodes, cnt);
if (!link) {
err = -ENOMEM;
@@ -3741,6 +3757,7 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
goto error;
link->nodes_cnt = cnt;
+ link->cookies = cookies;
err = bpf_trampoline_multi_attach(prog, ids, link);
kvfree(ids);
@@ -3751,6 +3768,7 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
return bpf_link_settle(&link_primer);
error:
+ kvfree(cookies);
kvfree(ids);
kvfree(link);
return err;
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 951a0122baaf..39407a77133b 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1874,6 +1874,7 @@ union bpf_attr {
} cgroup;
struct {
__aligned_u64 ids;
+ __aligned_u64 cookies;
__u32 cnt;
} tracing_multi;
};
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 15/29] bpf: Add support for tracing_multi link session
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (13 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 14/29] bpf: Add support for tracing_multi link cookies Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 16/29] bpf: Add support for tracing_multi link fdinfo Jiri Olsa
` (13 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding support to use session attachment with tracing_multi link.
Adding new BPF_TRACE_FSESSION_MULTI program attach type, that follows
the BPF_TRACE_FSESSION behaviour but on the tracing_multi link.
Such program is called on entry and exit of the attached function
and allows to pass cookie value from entry to exit execution.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
include/linux/bpf.h | 6 ++++-
include/uapi/linux/bpf.h | 1 +
kernel/bpf/fixups.c | 1 +
kernel/bpf/syscall.c | 1 +
kernel/bpf/trampoline.c | 44 +++++++++++++++++++++++++++-------
kernel/bpf/verifier.c | 19 +++++++++++----
kernel/trace/bpf_trace.c | 15 +++++++++++-
net/bpf/test_run.c | 1 +
tools/include/uapi/linux/bpf.h | 1 +
tools/lib/bpf/libbpf.c | 1 +
10 files changed, 75 insertions(+), 15 deletions(-)
diff --git a/include/linux/bpf.h b/include/linux/bpf.h
index 03d4ce0ef93e..ec94ac687728 100644
--- a/include/linux/bpf.h
+++ b/include/linux/bpf.h
@@ -1952,6 +1952,7 @@ struct bpf_tracing_multi_link {
struct bpf_link link;
struct bpf_tracing_multi_data data;
u64 *cookies;
+ struct bpf_tramp_node *fexits;
int nodes_cnt;
struct bpf_tracing_multi_node nodes[] __counted_by(nodes_cnt);
};
@@ -2139,7 +2140,8 @@ static inline void bpf_prog_put_recursion_context(struct bpf_prog *prog)
static inline bool is_tracing_multi(enum bpf_attach_type type)
{
- return type == BPF_TRACE_FENTRY_MULTI || type == BPF_TRACE_FEXIT_MULTI;
+ return type == BPF_TRACE_FENTRY_MULTI || type == BPF_TRACE_FEXIT_MULTI ||
+ type == BPF_TRACE_FSESSION_MULTI;
}
#if defined(CONFIG_BPF_JIT) && defined(CONFIG_BPF_SYSCALL)
@@ -2266,6 +2268,8 @@ static inline int bpf_fsession_cnt(struct bpf_tramp_nodes *nodes)
for (int i = 0; i < nodes[BPF_TRAMP_FENTRY].nr_nodes; i++) {
if (fentries.nodes[i]->link->prog->expected_attach_type == BPF_TRACE_FSESSION)
cnt++;
+ if (fentries.nodes[i]->link->prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI)
+ cnt++;
}
return cnt;
diff --git a/include/uapi/linux/bpf.h b/include/uapi/linux/bpf.h
index 39407a77133b..b49bed575ce3 100644
--- a/include/uapi/linux/bpf.h
+++ b/include/uapi/linux/bpf.h
@@ -1157,6 +1157,7 @@ enum bpf_attach_type {
BPF_TRACE_FSESSION,
BPF_TRACE_FENTRY_MULTI,
BPF_TRACE_FEXIT_MULTI,
+ BPF_TRACE_FSESSION_MULTI,
__MAX_BPF_ATTACH_TYPE
};
diff --git a/kernel/bpf/fixups.c b/kernel/bpf/fixups.c
index 1d4ea0beb076..a6ff666dc7dc 100644
--- a/kernel/bpf/fixups.c
+++ b/kernel/bpf/fixups.c
@@ -2187,6 +2187,7 @@ int bpf_do_misc_fixups(struct bpf_verifier_env *env)
if (eatype == BPF_TRACE_FEXIT ||
eatype == BPF_TRACE_FSESSION ||
eatype == BPF_TRACE_FEXIT_MULTI ||
+ eatype == BPF_TRACE_FSESSION_MULTI ||
eatype == BPF_MODIFY_RETURN) {
/* Load nr_args from ctx - 8 */
insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_0, BPF_REG_1, -8);
diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index 8fcdcb3c4eab..7a1baa367e64 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -4454,6 +4454,7 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type)
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FSESSION_MULTI:
case BPF_TRACE_FENTRY_MULTI:
case BPF_TRACE_FEXIT_MULTI:
case BPF_MODIFY_RETURN:
diff --git a/kernel/bpf/trampoline.c b/kernel/bpf/trampoline.c
index acccf52f6792..400b826eb2e1 100644
--- a/kernel/bpf/trampoline.c
+++ b/kernel/bpf/trampoline.c
@@ -183,7 +183,8 @@ bool bpf_prog_has_trampoline(const struct bpf_prog *prog)
case BPF_PROG_TYPE_TRACING:
if (eatype == BPF_TRACE_FENTRY || eatype == BPF_TRACE_FEXIT ||
eatype == BPF_MODIFY_RETURN || eatype == BPF_TRACE_FSESSION ||
- eatype == BPF_TRACE_FENTRY_MULTI || eatype == BPF_TRACE_FEXIT_MULTI)
+ eatype == BPF_TRACE_FENTRY_MULTI || eatype == BPF_TRACE_FEXIT_MULTI ||
+ eatype == BPF_TRACE_FSESSION_MULTI)
return true;
return false;
case BPF_PROG_TYPE_LSM:
@@ -790,6 +791,7 @@ static enum bpf_tramp_prog_type bpf_attach_type_to_tramp(struct bpf_prog *prog)
case BPF_TRACE_FEXIT_MULTI:
return BPF_TRAMP_FEXIT;
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FSESSION_MULTI:
return BPF_TRAMP_FSESSION;
case BPF_LSM_MAC:
if (!prog->aux->attach_func_proto->type)
@@ -822,13 +824,30 @@ static int bpf_freplace_check_tgt_prog(struct bpf_prog *tgt_prog)
return 0;
}
+static struct bpf_tramp_node *fsession_exit(struct bpf_tramp_node *node)
+{
+ if (node->link->type == BPF_LINK_TYPE_TRACING) {
+ struct bpf_tracing_link *link;
+
+ link = container_of(node->link, struct bpf_tracing_link, link.link);
+ return &link->fexit;
+ } else if (node->link->type == BPF_LINK_TYPE_TRACING_MULTI) {
+ struct bpf_tracing_multi_link *link;
+ struct bpf_tracing_multi_node *mnode;
+
+ link = container_of(node->link, struct bpf_tracing_multi_link, link);
+ mnode = container_of(node, struct bpf_tracing_multi_node, node);
+ return &link->fexits[mnode - link->nodes];
+ }
+ return NULL;
+}
+
static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
struct bpf_tramp_node *node,
int cnt)
{
- struct bpf_tracing_link *tr_link = NULL;
enum bpf_tramp_prog_type kind;
- struct bpf_tramp_node *node_existing;
+ struct bpf_tramp_node *node_existing, *fexit;
struct hlist_head *prog_list;
kind = bpf_attach_type_to_tramp(node->link->prog);
@@ -853,8 +872,10 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
hlist_add_head(&node->tramp_hlist, prog_list);
if (kind == BPF_TRAMP_FSESSION) {
tr->progs_cnt[BPF_TRAMP_FENTRY]++;
- tr_link = container_of(node, struct bpf_tracing_link, link.node);
- hlist_add_head(&tr_link->fexit.tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
+ fexit = fsession_exit(node);
+ if (WARN_ON_ONCE(!fexit))
+ return -EINVAL;
+ hlist_add_head(&fexit->tramp_hlist, &tr->progs_hlist[BPF_TRAMP_FEXIT]);
tr->progs_cnt[BPF_TRAMP_FEXIT]++;
} else {
tr->progs_cnt[kind]++;
@@ -865,13 +886,15 @@ static int bpf_trampoline_add_prog(struct bpf_trampoline *tr,
static void bpf_trampoline_remove_prog(struct bpf_trampoline *tr,
struct bpf_tramp_node *node)
{
- struct bpf_tracing_link *tr_link;
enum bpf_tramp_prog_type kind;
+ struct bpf_tramp_node *fexit;
kind = bpf_attach_type_to_tramp(node->link->prog);
if (kind == BPF_TRAMP_FSESSION) {
- tr_link = container_of(node, struct bpf_tracing_link, link.node);
- hlist_del_init(&tr_link->fexit.tramp_hlist);
+ fexit = fsession_exit(node);
+ if (WARN_ON_ONCE(!fexit))
+ return;
+ hlist_del_init(&fexit->tramp_hlist);
tr->progs_cnt[BPF_TRAMP_FEXIT]--;
kind = BPF_TRAMP_FENTRY;
}
@@ -1615,6 +1638,11 @@ int bpf_trampoline_multi_attach(struct bpf_prog *prog, u32 *ids,
mnode->node.link = &link->link;
mnode->node.cookie = link->cookies ? link->cookies[i] : 0;
+ if (prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI) {
+ link->fexits[i].link = &link->link;
+ link->fexits[i].cookie = link->cookies ? link->cookies[i] : 0;
+ }
+
cond_resched();
}
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c
index dca756034458..e2e34cc96133 100644
--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -16458,6 +16458,7 @@ static bool return_retval_range(struct bpf_verifier_env *env, struct bpf_retval_
case BPF_TRACE_FSESSION:
case BPF_TRACE_FENTRY_MULTI:
case BPF_TRACE_FEXIT_MULTI:
+ case BPF_TRACE_FSESSION_MULTI:
*range = retval_range(0, 0);
break;
case BPF_TRACE_RAW_TP:
@@ -19017,7 +19018,8 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
tgt_prog->expected_attach_type == BPF_TRACE_FEXIT ||
tgt_prog->expected_attach_type == BPF_TRACE_FENTRY_MULTI ||
tgt_prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI ||
- tgt_prog->expected_attach_type == BPF_TRACE_FSESSION)) {
+ tgt_prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ tgt_prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI)) {
/* Program extensions can extend all program types
* except fentry/fexit. The reason is the following.
* The fentry/fexit programs are used for performance
@@ -19123,9 +19125,11 @@ int bpf_check_attach_target(struct bpf_verifier_log *log,
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
case BPF_TRACE_FSESSION:
+ case BPF_TRACE_FSESSION_MULTI:
case BPF_TRACE_FENTRY_MULTI:
case BPF_TRACE_FEXIT_MULTI:
- if (prog->expected_attach_type == BPF_TRACE_FSESSION &&
+ if ((prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI) &&
!bpf_jit_supports_fsession()) {
bpf_log(log, "JIT does not support fsession\n");
return -EOPNOTSUPP;
@@ -19364,6 +19368,7 @@ static int check_attach_btf_id(struct bpf_verifier_env *env)
return -EINVAL;
} else if ((prog->expected_attach_type == BPF_TRACE_FEXIT ||
prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI ||
prog->expected_attach_type == BPF_MODIFY_RETURN) &&
btf_id_set_contains(&noreturn_deny, btf_id)) {
verbose(env, "Attaching fexit/fsession/fmod_ret to __noreturn function '%s' is rejected.\n",
@@ -19403,7 +19408,8 @@ int bpf_check_attach_btf_id_multi(struct btf *btf, struct bpf_prog *prog, u32 bt
return -EINVAL;
/* Check noreturn attachment. */
- if (prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI &&
+ if ((prog->expected_attach_type == BPF_TRACE_FEXIT_MULTI ||
+ prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI) &&
btf_id_set_contains(&noreturn_deny, btf_id))
return -EINVAL;
@@ -19683,7 +19689,9 @@ int bpf_fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
insn_buf[0] = BPF_MOV64_REG(BPF_REG_0, BPF_REG_1);
*cnt = 1;
} else if (desc->func_id == special_kfunc_list[KF_bpf_session_is_return] &&
- env->prog->expected_attach_type == BPF_TRACE_FSESSION) {
+ (env->prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ env->prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI)) {
+
/*
* inline the bpf_session_is_return() for fsession:
* bool bpf_session_is_return(void *ctx)
@@ -19696,7 +19704,8 @@ int bpf_fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn,
insn_buf[2] = BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1);
*cnt = 3;
} else if (desc->func_id == special_kfunc_list[KF_bpf_session_cookie] &&
- env->prog->expected_attach_type == BPF_TRACE_FSESSION) {
+ (env->prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ env->prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI)) {
/*
* inline bpf_session_cookie() for fsession:
* __u64 *bpf_session_cookie(void *ctx)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 6639751fab08..1a4d026d5d0c 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1334,7 +1334,8 @@ static inline bool is_uprobe_session(const struct bpf_prog *prog)
static inline bool is_trace_fsession(const struct bpf_prog *prog)
{
return prog->type == BPF_PROG_TYPE_TRACING &&
- prog->expected_attach_type == BPF_TRACE_FSESSION;
+ (prog->expected_attach_type == BPF_TRACE_FSESSION ||
+ prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI);
}
static const struct bpf_func_proto *
@@ -3659,6 +3660,7 @@ static void bpf_tracing_multi_link_dealloc(struct bpf_link *link)
struct bpf_tracing_multi_link *tr_link =
container_of(link, struct bpf_tracing_multi_link, link);
+ kvfree(tr_link->fexits);
kvfree(tr_link->cookies);
kvfree(tr_link);
}
@@ -3700,6 +3702,7 @@ static int check_dup_ids(u32 *ids, u32 cnt)
int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
{
struct bpf_tracing_multi_link *link = NULL;
+ struct bpf_tramp_node *fexits = NULL;
struct bpf_link_primer link_primer;
u32 cnt, *ids = NULL;
u64 __user *ucookies;
@@ -3743,6 +3746,14 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
}
}
+ if (prog->expected_attach_type == BPF_TRACE_FSESSION_MULTI) {
+ fexits = kvmalloc_objs(*fexits, cnt);
+ if (!fexits) {
+ err = -ENOMEM;
+ goto error;
+ }
+ }
+
link = kvzalloc_flex(*link, nodes, cnt);
if (!link) {
err = -ENOMEM;
@@ -3758,6 +3769,7 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
link->nodes_cnt = cnt;
link->cookies = cookies;
+ link->fexits = fexits;
err = bpf_trampoline_multi_attach(prog, ids, link);
kvfree(ids);
@@ -3768,6 +3780,7 @@ int bpf_tracing_multi_attach(struct bpf_prog *prog, const union bpf_attr *attr)
return bpf_link_settle(&link_primer);
error:
+ kvfree(fexits);
kvfree(cookies);
kvfree(ids);
kvfree(link);
diff --git a/net/bpf/test_run.c b/net/bpf/test_run.c
index 67769c700cae..a831682ee982 100644
--- a/net/bpf/test_run.c
+++ b/net/bpf/test_run.c
@@ -705,6 +705,7 @@ int bpf_prog_test_run_tracing(struct bpf_prog *prog,
case BPF_TRACE_FSESSION:
case BPF_TRACE_FENTRY_MULTI:
case BPF_TRACE_FEXIT_MULTI:
+ case BPF_TRACE_FSESSION_MULTI:
if (bpf_fentry_test1(1) != 2 ||
bpf_fentry_test2(2, 3) != 5 ||
bpf_fentry_test3(4, 5, 6) != 15 ||
diff --git a/tools/include/uapi/linux/bpf.h b/tools/include/uapi/linux/bpf.h
index 39407a77133b..b49bed575ce3 100644
--- a/tools/include/uapi/linux/bpf.h
+++ b/tools/include/uapi/linux/bpf.h
@@ -1157,6 +1157,7 @@ enum bpf_attach_type {
BPF_TRACE_FSESSION,
BPF_TRACE_FENTRY_MULTI,
BPF_TRACE_FEXIT_MULTI,
+ BPF_TRACE_FSESSION_MULTI,
__MAX_BPF_ATTACH_TYPE
};
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 7b99737590d1..2f5ac3e91d21 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -138,6 +138,7 @@ static const char * const attach_type_name[] = {
[BPF_TRACE_UPROBE_SESSION] = "trace_uprobe_session",
[BPF_TRACE_FENTRY_MULTI] = "trace_fentry_multi",
[BPF_TRACE_FEXIT_MULTI] = "trace_fexit_multi",
+ [BPF_TRACE_FSESSION_MULTI] = "trace_fsession_multi",
};
static const char * const link_type_name[] = {
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 16/29] bpf: Add support for tracing_multi link fdinfo
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (14 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 15/29] bpf: Add support for tracing_multi link session Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 17/29] libbpf: Add bpf_object_cleanup_btf function Jiri Olsa
` (12 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tracing_multi link fdinfo support with following output:
pos: 0
flags: 02000000
mnt_id: 19
ino: 3087
link_type: tracing_multi
link_id: 9
prog_tag: 599ba0e317244f86
prog_id: 94
attach_type: 59
cnt: 10
obj-id btf-id cookie func
1 91593 8 bpf_fentry_test1+0x4/0x10
1 91595 9 bpf_fentry_test2+0x4/0x10
1 91596 7 bpf_fentry_test3+0x4/0x20
1 91597 5 bpf_fentry_test4+0x4/0x20
1 91598 4 bpf_fentry_test5+0x4/0x20
1 91599 2 bpf_fentry_test6+0x4/0x20
1 91600 3 bpf_fentry_test7+0x4/0x10
1 91601 1 bpf_fentry_test8+0x4/0x10
1 91602 10 bpf_fentry_test9+0x4/0x10
1 91594 6 bpf_fentry_test10+0x4/0x10
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
kernel/trace/bpf_trace.c | 30 ++++++++++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 1a4d026d5d0c..be427a61dbfe 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3665,9 +3665,39 @@ static void bpf_tracing_multi_link_dealloc(struct bpf_link *link)
kvfree(tr_link);
}
+#ifdef CONFIG_PROC_FS
+static void bpf_tracing_multi_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_tracing_multi_link *tr_link =
+ container_of(link, struct bpf_tracing_multi_link, link);
+ bool has_cookies = !!tr_link->cookies;
+
+ seq_printf(seq, "attach_type:\t%u\n", tr_link->link.attach_type);
+ seq_printf(seq, "cnt:\t%u\n", tr_link->nodes_cnt);
+
+ seq_printf(seq, "%s\t %s\t %s\t %s\n", "obj-id", "btf-id", "cookie", "func");
+ for (int i = 0; i < tr_link->nodes_cnt; i++) {
+ struct bpf_tracing_multi_node *mnode = &tr_link->nodes[i];
+ u32 btf_id, obj_id;
+
+ bpf_trampoline_unpack_key(mnode->trampoline->key, &obj_id, &btf_id);
+ seq_printf(seq, "%u\t %u\t %llu\t %pS\n",
+ obj_id, btf_id,
+ has_cookies ? tr_link->cookies[i] : 0,
+ (void *) mnode->trampoline->ip);
+
+ cond_resched();
+ }
+}
+#endif
+
static const struct bpf_link_ops bpf_tracing_multi_link_lops = {
.release = bpf_tracing_multi_link_release,
.dealloc_deferred = bpf_tracing_multi_link_dealloc,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = bpf_tracing_multi_show_fdinfo,
+#endif
};
static int ids_cmp(const void *pa, const void *pb)
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 17/29] libbpf: Add bpf_object_cleanup_btf function
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (15 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 16/29] bpf: Add support for tracing_multi link fdinfo Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 18/29] libbpf: Add bpf_link_create support for tracing_multi link Jiri Olsa
` (11 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding bpf_object_cleanup_btf function to cleanup btf objects.
It will be used in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/lib/bpf/libbpf.c | 16 ++++++++++++----
1 file changed, 12 insertions(+), 4 deletions(-)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 2f5ac3e91d21..240cc37fe621 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -8940,13 +8940,10 @@ static void bpf_object_unpin(struct bpf_object *obj)
bpf_map__unpin(&obj->maps[i], NULL);
}
-static void bpf_object_post_load_cleanup(struct bpf_object *obj)
+static void bpf_object_cleanup_btf(struct bpf_object *obj)
{
int i;
- /* clean up fd_array */
- zfree(&obj->fd_array);
-
/* clean up module BTFs */
for (i = 0; i < obj->btf_module_cnt; i++) {
close(obj->btf_modules[i].fd);
@@ -8954,6 +8951,8 @@ static void bpf_object_post_load_cleanup(struct bpf_object *obj)
free(obj->btf_modules[i].name);
}
obj->btf_module_cnt = 0;
+ obj->btf_module_cap = 0;
+ obj->btf_modules_loaded = false;
zfree(&obj->btf_modules);
/* clean up vmlinux BTF */
@@ -8961,6 +8960,15 @@ static void bpf_object_post_load_cleanup(struct bpf_object *obj)
obj->btf_vmlinux = NULL;
}
+static void bpf_object_post_load_cleanup(struct bpf_object *obj)
+{
+ /* clean up fd_array */
+ zfree(&obj->fd_array);
+
+ /* clean up BTF */
+ bpf_object_cleanup_btf(obj);
+}
+
static int bpf_object_prepare(struct bpf_object *obj, const char *target_btf_path)
{
int err;
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 18/29] libbpf: Add bpf_link_create support for tracing_multi link
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (16 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 17/29] libbpf: Add bpf_object_cleanup_btf function Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 19/29] libbpf: Add btf_type_is_traceable_func function Jiri Olsa
` (10 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding bpf_link_create support for tracing_multi link with
new tracing_multi record in struct bpf_link_create_opts.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/lib/bpf/bpf.c | 9 +++++++++
tools/lib/bpf/bpf.h | 5 +++++
2 files changed, 14 insertions(+)
diff --git a/tools/lib/bpf/bpf.c b/tools/lib/bpf/bpf.c
index 3cd705802330..ff342972ca4a 100644
--- a/tools/lib/bpf/bpf.c
+++ b/tools/lib/bpf/bpf.c
@@ -843,6 +843,15 @@ int bpf_link_create(int prog_fd, int target_fd,
if (!OPTS_ZEROED(opts, uprobe_multi))
return libbpf_err(-EINVAL);
break;
+ case BPF_TRACE_FENTRY_MULTI:
+ case BPF_TRACE_FEXIT_MULTI:
+ case BPF_TRACE_FSESSION_MULTI:
+ attr.link_create.tracing_multi.ids = ptr_to_u64(OPTS_GET(opts, tracing_multi.ids, 0));
+ attr.link_create.tracing_multi.cookies = ptr_to_u64(OPTS_GET(opts, tracing_multi.cookies, 0));
+ attr.link_create.tracing_multi.cnt = OPTS_GET(opts, tracing_multi.cnt, 0);
+ if (!OPTS_ZEROED(opts, tracing_multi))
+ return libbpf_err(-EINVAL);
+ break;
case BPF_TRACE_RAW_TP:
case BPF_TRACE_FENTRY:
case BPF_TRACE_FEXIT:
diff --git a/tools/lib/bpf/bpf.h b/tools/lib/bpf/bpf.h
index 2312900a3263..012354131cf6 100644
--- a/tools/lib/bpf/bpf.h
+++ b/tools/lib/bpf/bpf.h
@@ -469,6 +469,11 @@ struct bpf_link_create_opts {
__u32 relative_id;
__u64 expected_revision;
} cgroup;
+ struct {
+ const __u32 *ids;
+ const __u64 *cookies;
+ __u32 cnt;
+ } tracing_multi;
};
size_t :0;
};
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 19/29] libbpf: Add btf_type_is_traceable_func function
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (17 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 18/29] libbpf: Add bpf_link_create support for tracing_multi link Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 20/29] libbpf: Add support to create tracing multi link Jiri Olsa
` (9 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding btf_type_is_traceable_func function to perform same checks
as the kernel's btf_distill_func_proto function to prevent attachment
on some of the functions.
Exporting the function via libbpf_internal.h because it will be used
by benchmark test in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/lib/bpf/libbpf.c | 79 +++++++++++++++++++++++++++++++++
tools/lib/bpf/libbpf_internal.h | 1 +
2 files changed, 80 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 240cc37fe621..df833ddda0ea 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -12449,6 +12449,85 @@ static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, stru
return ret;
}
+#define MAX_BPF_FUNC_ARGS 12
+
+static bool btf_type_is_modifier(const struct btf_type *t)
+{
+ switch (BTF_INFO_KIND(t->info)) {
+ case BTF_KIND_TYPEDEF:
+ case BTF_KIND_VOLATILE:
+ case BTF_KIND_CONST:
+ case BTF_KIND_RESTRICT:
+ case BTF_KIND_TYPE_TAG:
+ return true;
+ default:
+ return false;
+ }
+}
+
+#define MAX_RESOLVE_DEPTH 32
+
+static int btf_get_type_size(const struct btf *btf, __u32 type_id,
+ const struct btf_type **ret_type)
+{
+ const struct btf_type *t;
+ int i;
+
+ *ret_type = btf__type_by_id(btf, 0);
+ if (!type_id)
+ return 0;
+ t = btf__type_by_id(btf, type_id);
+ for (i = 0; i < MAX_RESOLVE_DEPTH && t && btf_type_is_modifier(t); i++)
+ t = btf__type_by_id(btf, t->type);
+ if (!t || i == MAX_RESOLVE_DEPTH)
+ return -EINVAL;
+ *ret_type = t;
+ if (btf_is_ptr(t))
+ return btf__pointer_size(btf);
+ if (btf_is_int(t) || btf_is_any_enum(t) || btf_is_struct(t) || btf_is_union(t))
+ return t->size;
+ return -EINVAL;
+}
+
+bool btf_type_is_traceable_func(const struct btf *btf, const struct btf_type *t)
+{
+ const struct btf_param *args;
+ const struct btf_type *proto;
+ __u32 i, nargs;
+ int ret;
+
+ if (!btf_is_func(t))
+ return false;
+ proto = btf__type_by_id(btf, t->type);
+ if (!proto || !btf_is_func_proto(proto))
+ return false;
+
+ args = (const struct btf_param *)(proto + 1);
+ nargs = btf_vlen(proto);
+ if (nargs > MAX_BPF_FUNC_ARGS)
+ return false;
+
+ /* No support for struct return type. */
+ ret = btf_get_type_size(btf, proto->type, &t);
+ if (ret < 0 || btf_is_struct(t) || btf_is_union(t))
+ return false;
+
+ for (i = 0; i < nargs; i++) {
+ /* No support for variable args. */
+ if (i == nargs - 1 && args[i].type == 0)
+ return false;
+ ret = btf_get_type_size(btf, args[i].type, &t);
+ /* No support of struct argument size greater than 16 bytes. */
+ if (ret < 0 || ret > 16)
+ return false;
+ /* No support for void argument. */
+ if (ret == 0)
+ return false;
+ }
+
+ return true;
+}
+
static inline int add_uprobe_event_legacy(const char *probe_name, bool retprobe,
const char *binary_path, size_t offset)
{
diff --git a/tools/lib/bpf/libbpf_internal.h b/tools/lib/bpf/libbpf_internal.h
index 7d93c6c01d60..04cd303fb5a8 100644
--- a/tools/lib/bpf/libbpf_internal.h
+++ b/tools/lib/bpf/libbpf_internal.h
@@ -250,6 +250,7 @@ const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, __u32 id, _
const struct btf_header *btf_header(const struct btf *btf);
void btf_set_base_btf(struct btf *btf, const struct btf *base_btf);
int btf_relocate(struct btf *btf, const struct btf *base_btf, __u32 **id_map);
+bool btf_type_is_traceable_func(const struct btf *btf, const struct btf_type *t);
static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t)
{
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 20/29] libbpf: Add support to create tracing multi link
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (18 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 19/29] libbpf: Add btf_type_is_traceable_func function Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 21/29] selftests/bpf: Add tracing multi skel/pattern/ids attach tests Jiri Olsa
` (8 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding bpf_program__attach_tracing_multi function for attaching
tracing program to multiple functions.
struct bpf_link *
bpf_program__attach_tracing_multi(const struct bpf_program *prog,
const char *pattern,
const struct bpf_tracing_multi_opts *opts);
User can specify functions to attach with 'pattern' argument that
allows wildcards (*?' supported) or provide BTF ids of functions
in array directly via opts argument. These options are mutually
exclusive.
When using BTF ids, user can also provide cookie value for each
provided id/function, that can be retrieved later in bpf program
with bpf_get_attach_cookie helper. Each cookie value is paired with
provided BTF id with the same array index.
Adding support to auto attach programs with following sections:
fsession.multi/<pattern>
fsession.multi.s/<pattern>
fentry.multi/<pattern>
fexit.multi/<pattern>
fentry.multi.s/<pattern>
fexit.multi.s/<pattern>
The provided <pattern> is used as 'pattern' argument in
bpf_program__attach_kprobe_multi_opts function.
The <pattern> allows to specify optional kernel module name with
following syntax:
<module>:<function_pattern>
In order to attach tracing_multi link to a module functions:
- program must be loaded with 'module' btf fd
(in attr::attach_btf_obj_fd)
- bpf_program__attach_tracing_multi must either have
pattern with module spec or BTF ids from the module
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/lib/bpf/libbpf.c | 275 +++++++++++++++++++++++++++++++++++++++
tools/lib/bpf/libbpf.h | 15 +++
tools/lib/bpf/libbpf.map | 1 +
3 files changed, 291 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index df833ddda0ea..120633730fa9 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -7771,6 +7771,69 @@ static int bpf_object__sanitize_prog(struct bpf_object *obj, struct bpf_program
static int libbpf_find_attach_btf_id(struct bpf_program *prog, const char *attach_name,
int *btf_obj_fd, int *btf_type_id);
+static inline bool is_tracing_multi(enum bpf_attach_type type)
+{
+ return type == BPF_TRACE_FENTRY_MULTI || type == BPF_TRACE_FEXIT_MULTI ||
+ type == BPF_TRACE_FSESSION_MULTI;
+}
+
+static const struct module_btf *find_attach_module(struct bpf_object *obj, const char *attach)
+{
+ const char *sep, *mod_name = NULL;
+ int i, mod_len, err;
+
+ /*
+ * We expect attach string in the form of either
+ * - function_pattern or
+ * - <module>:function_pattern
+ */
+ sep = strchr(attach, ':');
+ if (sep) {
+ mod_name = attach;
+ mod_len = sep - mod_name;
+ }
+ if (!mod_name)
+ return NULL;
+
+ err = load_module_btfs(obj);
+ if (err)
+ return NULL;
+
+ for (i = 0; i < obj->btf_module_cnt; i++) {
+ const struct module_btf *mod = &obj->btf_modules[i];
+
+ if (strncmp(mod->name, mod_name, mod_len) == 0 && mod->name[mod_len] == '\0')
+ return mod;
+ }
+ return NULL;
+}
+
+static int tracing_multi_mod_fd(struct bpf_program *prog, int *btf_obj_fd)
+{
+ const char *attach_name, *sep;
+ const struct module_btf *mod;
+
+ *btf_obj_fd = 0;
+ attach_name = strchr(prog->sec_name, '/');
+
+ /* Program with no details in spec, using kernel btf. */
+ if (!attach_name)
+ return 0;
+
+ /* Program with no module section, using kernel btf. */
+ sep = strchr(++attach_name, ':');
+ if (!sep)
+ return 0;
+
+ /* Program with module specified, get its btf fd. */
+ mod = find_attach_module(prog->obj, attach_name);
+ if (!mod)
+ return -EINVAL;
+
+ *btf_obj_fd = mod->fd;
+ return 0;
+}
+
/* this is called as prog->sec_def->prog_prepare_load_fn for libbpf-supported sec_defs */
static int libbpf_prepare_prog_load(struct bpf_program *prog,
struct bpf_prog_load_opts *opts, long cookie)
@@ -7834,6 +7897,18 @@ static int libbpf_prepare_prog_load(struct bpf_program *prog,
opts->attach_btf_obj_fd = btf_obj_fd;
opts->attach_btf_id = btf_type_id;
}
+
+ if (is_tracing_multi(prog->expected_attach_type)) {
+ int err, btf_obj_fd = 0;
+
+ err = tracing_multi_mod_fd(prog, &btf_obj_fd);
+ if (err < 0)
+ return err;
+
+ prog->attach_btf_obj_fd = btf_obj_fd;
+ opts->attach_btf_obj_fd = btf_obj_fd;
+ }
+
return 0;
}
@@ -9995,6 +10070,7 @@ static int attach_kprobe_session(const struct bpf_program *prog, long cookie, st
static int attach_uprobe_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_lsm(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static int attach_iter(const struct bpf_program *prog, long cookie, struct bpf_link **link);
+static int attach_tracing_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link);
static const struct bpf_sec_def section_defs[] = {
SEC_DEF("socket", SOCKET_FILTER, 0, SEC_NONE),
@@ -10048,6 +10124,12 @@ static const struct bpf_sec_def section_defs[] = {
SEC_DEF("fexit.s+", TRACING, BPF_TRACE_FEXIT, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
SEC_DEF("fsession+", TRACING, BPF_TRACE_FSESSION, SEC_ATTACH_BTF, attach_trace),
SEC_DEF("fsession.s+", TRACING, BPF_TRACE_FSESSION, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_trace),
+ SEC_DEF("fsession.multi+", TRACING, BPF_TRACE_FSESSION_MULTI, 0, attach_tracing_multi),
+ SEC_DEF("fsession.multi.s+", TRACING, BPF_TRACE_FSESSION_MULTI, SEC_SLEEPABLE, attach_tracing_multi),
+ SEC_DEF("fentry.multi+", TRACING, BPF_TRACE_FENTRY_MULTI, 0, attach_tracing_multi),
+ SEC_DEF("fexit.multi+", TRACING, BPF_TRACE_FEXIT_MULTI, 0, attach_tracing_multi),
+ SEC_DEF("fentry.multi.s+", TRACING, BPF_TRACE_FENTRY_MULTI, SEC_SLEEPABLE, attach_tracing_multi),
+ SEC_DEF("fexit.multi.s+", TRACING, BPF_TRACE_FEXIT_MULTI, SEC_SLEEPABLE, attach_tracing_multi),
SEC_DEF("freplace+", EXT, 0, SEC_ATTACH_BTF, attach_trace),
SEC_DEF("lsm+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF, attach_lsm),
SEC_DEF("lsm.s+", LSM, BPF_LSM_MAC, SEC_ATTACH_BTF | SEC_SLEEPABLE, attach_lsm),
@@ -12528,6 +12610,199 @@ bool btf_type_is_traceable_func(const struct btf *btf, const struct btf_type *t)
return true;
}
+static int
+collect_btf_func_ids_by_glob(const struct btf *btf, const char *pattern, __u32 **ids)
+{
+ __u32 type_id, nr_types = btf__type_cnt(btf);
+ size_t cap = 0, cnt = 0;
+
+ if (!pattern)
+ return -EINVAL;
+
+ for (type_id = 1; type_id < nr_types; type_id++) {
+ const struct btf_type *t = btf__type_by_id(btf, type_id);
+ const char *name;
+ int err;
+
+ if (btf_kind(t) != BTF_KIND_FUNC)
+ continue;
+ name = btf__name_by_offset(btf, t->name_off);
+ if (!name)
+ continue;
+
+ if (!glob_match(name, pattern))
+ continue;
+ if (!btf_type_is_traceable_func(btf, t))
+ continue;
+
+ err = libbpf_ensure_mem((void **) ids, &cap, sizeof(**ids), cnt + 1);
+ if (err) {
+ free(*ids);
+ return -ENOMEM;
+ }
+ (*ids)[cnt++] = type_id;
+ }
+
+ return cnt;
+}
+
+static int collect_func_ids_by_glob(const struct bpf_program *prog, const char *pattern, __u32 **ids)
+{
+ struct bpf_object *obj = prog->obj;
+ const struct module_btf *mod;
+ struct btf *btf = NULL;
+ const char *sep;
+ int err;
+
+ err = bpf_object__load_vmlinux_btf(obj, true);
+ if (err)
+ return err;
+
+ /* In case we have module specified, we will find its btf and use that. */
+ sep = strchr(pattern, ':');
+ if (sep) {
+ mod = find_attach_module(obj, pattern);
+ if (!mod) {
+ err = -EINVAL;
+ goto cleanup;
+ }
+ btf = mod->btf;
+ pattern = sep + 1;
+ } else {
+ /* Program is loaded for kernel module. */
+ if (prog->attach_btf_obj_fd) {
+ err = -EINVAL;
+ goto cleanup;
+ }
+ btf = obj->btf_vmlinux;
+ }
+
+ err = collect_btf_func_ids_by_glob(btf, pattern, ids);
+
+cleanup:
+ bpf_object_cleanup_btf(obj);
+ return err;
+}
+
+struct bpf_link *
+bpf_program__attach_tracing_multi(const struct bpf_program *prog, const char *pattern,
+ const struct bpf_tracing_multi_opts *opts)
+{
+ LIBBPF_OPTS(bpf_link_create_opts, lopts);
+ int prog_fd, link_fd, err, cnt;
+ __u32 *ids, *free_ids = NULL;
+ struct bpf_link *link;
+ __u64 *cookies;
+
+ if (!OPTS_VALID(opts, bpf_tracing_multi_opts))
+ return libbpf_err_ptr(-EINVAL);
+
+ prog_fd = bpf_program__fd(prog);
+ if (prog_fd < 0) {
+ pr_warn("prog '%s': can't attach BPF program without FD (was it loaded?)\n",
+ prog->name);
+ return libbpf_err_ptr(-EINVAL);
+ }
+
+ cnt = OPTS_GET(opts, cnt, 0);
+ ids = OPTS_GET(opts, ids, NULL);
+ cookies = OPTS_GET(opts, cookies, NULL);
+
+ if (!!ids != !!cnt)
+ return libbpf_err_ptr(-EINVAL);
+ if (pattern && (ids || cookies))
+ return libbpf_err_ptr(-EINVAL);
+ if (!pattern && !ids)
+ return libbpf_err_ptr(-EINVAL);
+
+ if (pattern) {
+ cnt = collect_func_ids_by_glob(prog, pattern, &ids);
+ if (cnt < 0)
+ return libbpf_err_ptr(cnt);
+ if (cnt == 0)
+ return libbpf_err_ptr(-EINVAL);
+ free_ids = ids;
+ }
+
+ lopts.tracing_multi.ids = ids;
+ lopts.tracing_multi.cookies = cookies;
+ lopts.tracing_multi.cnt = cnt;
+
+ link = calloc(1, sizeof(*link));
+ if (!link) {
+ err = -ENOMEM;
+ goto error;
+ }
+ link->detach = &bpf_link__detach_fd;
+
+ link_fd = bpf_link_create(prog_fd, 0, prog->expected_attach_type, &lopts);
+ if (link_fd < 0) {
+ err = -errno;
+ pr_warn("prog '%s': failed to attach: %s\n", prog->name, errstr(err));
+ goto error;
+ }
+ link->fd = link_fd;
+ free(free_ids);
+ return link;
+
+error:
+ free(link);
+ free(free_ids);
+ return libbpf_err_ptr(err);
+}
+
+static int attach_tracing_multi(const struct bpf_program *prog, long cookie, struct bpf_link **link)
+{
+ static const char *const prefixes[] = {
+ "fentry.multi",
+ "fexit.multi",
+ "fsession.multi",
+ "fentry.multi.s",
+ "fexit.multi.s",
+ "fsession.multi.s",
+ };
+ const char *spec = NULL;
+ char *pattern;
+ size_t i;
+ int n;
+
+ *link = NULL;
+
+ for (i = 0; i < ARRAY_SIZE(prefixes); i++) {
+ size_t pfx_len;
+
+ if (!str_has_pfx(prog->sec_name, prefixes[i]))
+ continue;
+
+ pfx_len = strlen(prefixes[i]);
+ /* no auto-attach case of, e.g., SEC("fentry.multi") */
+ if (prog->sec_name[pfx_len] == '\0')
+ return 0;
+
+ if (prog->sec_name[pfx_len] != '/')
+ continue;
+
+ spec = prog->sec_name + pfx_len + 1;
+ break;
+ }
+
+ if (!spec) {
+ pr_warn("prog '%s': invalid section name '%s'\n",
+ prog->name, prog->sec_name);
+ return -EINVAL;
+ }
+
+ n = sscanf(spec, "%m[a-zA-Z0-9_.*?:]", &pattern);
+ if (n < 1) {
+ pr_warn("tracing multi pattern is invalid: %s\n", spec);
+ return -EINVAL;
+ }
+
+ *link = bpf_program__attach_tracing_multi(prog, pattern, NULL);
+ free(pattern);
+ return libbpf_get_error(*link);
+}
+
static inline int add_uprobe_event_legacy(const char *probe_name, bool retprobe,
const char *binary_path, size_t offset)
{
diff --git a/tools/lib/bpf/libbpf.h b/tools/lib/bpf/libbpf.h
index bba4e8464396..2ed8afec0aac 100644
--- a/tools/lib/bpf/libbpf.h
+++ b/tools/lib/bpf/libbpf.h
@@ -726,6 +726,21 @@ bpf_program__attach_ksyscall(const struct bpf_program *prog,
const char *syscall_name,
const struct bpf_ksyscall_opts *opts);
+struct bpf_tracing_multi_opts {
+ /* size of this struct, for forward/backward compatibility */
+ size_t sz;
+ __u32 *ids;
+ __u64 *cookies;
+ size_t cnt;
+ size_t :0;
+};
+
+#define bpf_tracing_multi_opts__last_field cnt
+
+LIBBPF_API struct bpf_link *
+bpf_program__attach_tracing_multi(const struct bpf_program *prog, const char *pattern,
+ const struct bpf_tracing_multi_opts *opts);
+
struct bpf_uprobe_opts {
/* size of this struct, for forward/backward compatibility */
size_t sz;
diff --git a/tools/lib/bpf/libbpf.map b/tools/lib/bpf/libbpf.map
index dfed8d60af05..b731df19ae69 100644
--- a/tools/lib/bpf/libbpf.map
+++ b/tools/lib/bpf/libbpf.map
@@ -458,6 +458,7 @@ LIBBPF_1.7.0 {
LIBBPF_1.8.0 {
global:
+ bpf_program__attach_tracing_multi;
bpf_program__clone;
btf__new_empty_opts;
} LIBBPF_1.7.0;
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 21/29] selftests/bpf: Add tracing multi skel/pattern/ids attach tests
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (19 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 20/29] libbpf: Add support to create tracing multi link Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 22/29] selftests/bpf: Add tracing multi skel/pattern/ids module " Jiri Olsa
` (7 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for tracing_multi link attachment via all possible
libbpf apis - skeleton, function pattern and btf ids.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/testing/selftests/bpf/Makefile | 3 +-
.../selftests/bpf/prog_tests/tracing_multi.c | 257 ++++++++++++++++++
.../bpf/progs/tracing_multi_attach.c | 39 +++
.../selftests/bpf/progs/tracing_multi_check.c | 151 ++++++++++
4 files changed, 449 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/prog_tests/tracing_multi.c
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_attach.c
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_check.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index bc049620c774..396b68f862fe 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -500,7 +500,7 @@ SKEL_BLACKLIST := btf__% test_pinning_invalid.c test_sk_assign.c
LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \
linked_vars.skel.h linked_maps.skel.h \
test_subskeleton.skel.h test_subskeleton_lib.skel.h \
- test_usdt.skel.h
+ test_usdt.skel.h tracing_multi.skel.h
LSKELS := fexit_sleep.c trace_printk.c trace_vprintk.c map_ptr_kern.c \
core_kern.c core_kern_overflow.c test_ringbuf.c \
@@ -526,6 +526,7 @@ test_usdt.skel.h-deps := test_usdt.bpf.o test_usdt_multispec.bpf.o
xsk_xdp_progs.skel.h-deps := xsk_xdp_progs.bpf.o
xdp_hw_metadata.skel.h-deps := xdp_hw_metadata.bpf.o
xdp_features.skel.h-deps := xdp_features.bpf.o
+tracing_multi.skel.h-deps := tracing_multi_attach.bpf.o tracing_multi_check.bpf.o
LINKED_BPF_OBJS := $(foreach skel,$(LINKED_SKELS),$($(skel)-deps))
LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.c,$(LINKED_BPF_OBJS))
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
new file mode 100644
index 000000000000..e290513358d9
--- /dev/null
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -0,0 +1,257 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <test_progs.h>
+#include <bpf/btf.h>
+#include <search.h>
+#include "bpf/libbpf_internal.h"
+#include "tracing_multi.skel.h"
+#include "trace_helpers.h"
+
+static const char * const bpf_fentry_test[] = {
+ "bpf_fentry_test1",
+ "bpf_fentry_test2",
+ "bpf_fentry_test3",
+ "bpf_fentry_test4",
+ "bpf_fentry_test5",
+ "bpf_fentry_test6",
+ "bpf_fentry_test7",
+ "bpf_fentry_test8",
+ "bpf_fentry_test9",
+ "bpf_fentry_test10",
+};
+
+#define FUNCS_CNT (ARRAY_SIZE(bpf_fentry_test))
+
+static int compare(const void *ppa, const void *ppb)
+{
+ const char *pa = *(const char **) ppa;
+ const char *pb = *(const char **) ppb;
+
+ return strcmp(pa, pb);
+}
+
+static void tdestroy_free_nop(void *ptr)
+{
+}
+
+static __u32 *get_ids(const char * const funcs[], int funcs_cnt, const char *mod)
+{
+ struct btf *btf, *vmlinux_btf = NULL;
+ __u32 nr, type_id, cnt = 0;
+ void *root = NULL;
+ __u32 *ids = NULL;
+ int i, err = 0;
+
+ btf = btf__load_vmlinux_btf();
+ if (!ASSERT_OK_PTR(btf, "btf__load_vmlinux_btf"))
+ return NULL;
+
+ if (mod) {
+ vmlinux_btf = btf;
+ btf = btf__load_module_btf(mod, vmlinux_btf);
+ if (!ASSERT_OK_PTR(btf, "btf__load_module_btf")) {
+ btf__free(vmlinux_btf);
+ return NULL;
+ }
+ }
+
+ ids = calloc(funcs_cnt, sizeof(ids[0]));
+ if (!ids)
+ goto out;
+
+ /*
+ * We sort function names by name and search them
+ * below for each function.
+ */
+ for (i = 0; i < funcs_cnt; i++) {
+ if (!tsearch(&funcs[i], &root, compare)) {
+ ASSERT_FAIL("tsearch failed");
+ err = -1;
+ goto out;
+ }
+ }
+
+ nr = btf__type_cnt(btf);
+ for (type_id = 1; type_id < nr && cnt < funcs_cnt; type_id++) {
+ const struct btf_type *type;
+ const char *str, ***val;
+ unsigned int idx;
+
+ type = btf__type_by_id(btf, type_id);
+ if (!type) {
+ err = -1;
+ break;
+ }
+
+ if (BTF_INFO_KIND(type->info) != BTF_KIND_FUNC)
+ continue;
+
+ str = btf__name_by_offset(btf, type->name_off);
+ if (!str) {
+ err = -1;
+ break;
+ }
+
+ val = tfind(&str, &root, compare);
+ if (!val)
+ continue;
+
+ /*
+ * We keep pointer for each function name so we can get the original
+ * array index and have the resulting ids array matching the original
+ * function array.
+ *
+ * Doing it this way allow us to easily test the cookies support,
+ * because each cookie is attached to particular function/id.
+ */
+ idx = *val - funcs;
+ ids[idx] = type_id;
+ cnt++;
+ }
+
+ if (err) {
+ free(ids);
+ ids = NULL;
+ }
+
+out:
+ tdestroy(root, tdestroy_free_nop);
+ btf__free(vmlinux_btf);
+ btf__free(btf);
+ return ids;
+}
+
+static void tracing_multi_test_run(struct tracing_multi *skel)
+{
+ LIBBPF_OPTS(bpf_test_run_opts, topts);
+ int err, prog_fd;
+
+ prog_fd = bpf_program__fd(skel->progs.test_fentry);
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run");
+
+ /* extra +1 count for sleepable programs */
+ ASSERT_EQ(skel->bss->test_result_fentry, FUNCS_CNT + 1, "test_result_fentry");
+ ASSERT_EQ(skel->bss->test_result_fexit, FUNCS_CNT + 1, "test_result_fexit");
+}
+
+static void test_skel_api(void)
+{
+ struct tracing_multi *skel;
+ int err;
+
+ skel = tracing_multi__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ err = tracing_multi__attach(skel);
+ if (!ASSERT_OK(err, "tracing_multi__attach"))
+ goto cleanup;
+
+ tracing_multi_test_run(skel);
+
+cleanup:
+ tracing_multi__destroy(skel);
+}
+
+static void test_link_api_pattern(void)
+{
+ struct tracing_multi *skel;
+
+ skel = tracing_multi__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ "bpf_fentry_test*", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ "bpf_fentry_test*", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fentry_s = bpf_program__attach_tracing_multi(skel->progs.test_fentry_s,
+ "bpf_fentry_test1", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry_s, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit_s = bpf_program__attach_tracing_multi(skel->progs.test_fexit_s,
+ "bpf_fentry_test1", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit_s, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ tracing_multi_test_run(skel);
+
+cleanup:
+ tracing_multi__destroy(skel);
+}
+
+static void test_link_api_ids(void)
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi *skel;
+ size_t cnt = FUNCS_CNT;
+ __u32 *ids;
+
+ skel = tracing_multi__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ ids = get_ids(bpf_fentry_test, cnt, NULL);
+ if (!ASSERT_OK_PTR(ids, "get_ids"))
+ goto cleanup;
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ /* Only bpf_fentry_test1 is allowed for sleepable programs. */
+ opts.cnt = 1;
+ skel->links.test_fentry_s = bpf_program__attach_tracing_multi(skel->progs.test_fentry_s,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry_s, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit_s = bpf_program__attach_tracing_multi(skel->progs.test_fexit_s,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit_s, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ tracing_multi_test_run(skel);
+
+cleanup:
+ tracing_multi__destroy(skel);
+ free(ids);
+}
+
+void test_tracing_multi_test(void)
+{
+#ifndef __x86_64__
+ test__skip();
+ return;
+#endif
+
+ if (test__start_subtest("skel_api"))
+ test_skel_api();
+ if (test__start_subtest("link_api_pattern"))
+ test_link_api_pattern();
+ if (test__start_subtest("link_api_ids"))
+ test_link_api_ids();
+}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_attach.c b/tools/testing/selftests/bpf/progs/tracing_multi_attach.c
new file mode 100644
index 000000000000..332d0a423a43
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_attach.c
@@ -0,0 +1,39 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__hidden extern int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return);
+
+__u64 test_result_fentry = 0;
+__u64 test_result_fexit = 0;
+
+SEC("fentry.multi/bpf_fentry_test*")
+int BPF_PROG(test_fentry)
+{
+ tracing_multi_arg_check(ctx, &test_result_fentry, false);
+ return 0;
+}
+
+SEC("fexit.multi/bpf_fentry_test*")
+int BPF_PROG(test_fexit)
+{
+ tracing_multi_arg_check(ctx, &test_result_fexit, true);
+ return 0;
+}
+
+SEC("fentry.multi.s/bpf_fentry_test1")
+int BPF_PROG(test_fentry_s)
+{
+ tracing_multi_arg_check(ctx, &test_result_fentry, false);
+ return 0;
+}
+
+SEC("fexit.multi.s/bpf_fentry_test1")
+int BPF_PROG(test_fexit_s)
+{
+ tracing_multi_arg_check(ctx, &test_result_fexit, true);
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_check.c b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
new file mode 100644
index 000000000000..333a3a7bae8a
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
@@ -0,0 +1,151 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+int pid = 0;
+
+/* bpf_fentry_test1 is exported as kfunc via vmlinux.h */
+extern const void bpf_fentry_test2 __ksym;
+extern const void bpf_fentry_test3 __ksym;
+extern const void bpf_fentry_test4 __ksym;
+extern const void bpf_fentry_test5 __ksym;
+extern const void bpf_fentry_test6 __ksym;
+extern const void bpf_fentry_test7 __ksym;
+extern const void bpf_fentry_test8 __ksym;
+extern const void bpf_fentry_test9 __ksym;
+extern const void bpf_fentry_test10 __ksym;
+
+int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
+{
+ void *ip = (void *) bpf_get_func_ip(ctx);
+ __u64 value = 0, ret = 0;
+ long err = 0;
+
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 1;
+
+ if (is_return)
+ err |= bpf_get_func_ret(ctx, &ret);
+
+ if (ip == &bpf_fentry_test1) {
+ int a;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (int) value;
+
+ err |= is_return ? ret != 2 : 0;
+
+ *test_result += err == 0 && a == 1;
+ } else if (ip == &bpf_fentry_test2) {
+ __u64 b;
+ int a;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (int) value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = value;
+
+ err |= is_return ? ret != 5 : 0;
+
+ *test_result += err == 0 && a == 2 && b == 3;
+ } else if (ip == &bpf_fentry_test3) {
+ __u64 c;
+ char a;
+ int b;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (char) value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (int) value;
+ err |= bpf_get_func_arg(ctx, 2, &value);
+ c = value;
+
+ err |= is_return ? ret != 15 : 0;
+
+ *test_result += err == 0 && a == 4 && b == 5 && c == 6;
+ } else if (ip == &bpf_fentry_test4) {
+ void *a;
+ char b;
+ int c;
+ __u64 d;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (void *) value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (char) value;
+ err |= bpf_get_func_arg(ctx, 2, &value);
+ c = (int) value;
+ err |= bpf_get_func_arg(ctx, 3, &value);
+ d = value;
+
+ err |= is_return ? ret != 34 : 0;
+
+ *test_result += err == 0 && a == (void *) 7 && b == 8 && c == 9 && d == 10;
+ } else if (ip == &bpf_fentry_test5) {
+ __u64 a;
+ void *b;
+ short c;
+ int d;
+ __u64 e;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (void *) value;
+ err |= bpf_get_func_arg(ctx, 2, &value);
+ c = (short) value;
+ err |= bpf_get_func_arg(ctx, 3, &value);
+ d = (int) value;
+ err |= bpf_get_func_arg(ctx, 4, &value);
+ e = value;
+
+ err |= is_return ? ret != 65 : 0;
+
+ *test_result += err == 0 && a == 11 && b == (void *) 12 && c == 13 && d == 14 && e == 15;
+ } else if (ip == &bpf_fentry_test6) {
+ __u64 a;
+ void *b;
+ short c;
+ int d;
+ void *e;
+ __u64 f;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (void *) value;
+ err |= bpf_get_func_arg(ctx, 2, &value);
+ c = (short) value;
+ err |= bpf_get_func_arg(ctx, 3, &value);
+ d = (int) value;
+ err |= bpf_get_func_arg(ctx, 4, &value);
+ e = (void *) value;
+ err |= bpf_get_func_arg(ctx, 5, &value);
+ f = value;
+
+ err |= is_return ? ret != 111 : 0;
+
+ *test_result += err == 0 && a == 16 && b == (void *) 17 && c == 18 && d == 19 && e == (void *) 20 && f == 21;
+ } else if (ip == &bpf_fentry_test7) {
+ err |= is_return ? ret != 0 : 0;
+
+ *test_result += err == 0 ? 1 : 0;
+ } else if (ip == &bpf_fentry_test8) {
+ err |= is_return ? ret != 0 : 0;
+
+ *test_result += err == 0 ? 1 : 0;
+ } else if (ip == &bpf_fentry_test9) {
+ err |= is_return ? ret != 0 : 0;
+
+ *test_result += err == 0 ? 1 : 0;
+ } else if (ip == &bpf_fentry_test10) {
+ err |= is_return ? ret != 0 : 0;
+
+ *test_result += err == 0 ? 1 : 0;
+ }
+
+ return 0;
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 22/29] selftests/bpf: Add tracing multi skel/pattern/ids module attach tests
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (20 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 21/29] selftests/bpf: Add tracing multi skel/pattern/ids attach tests Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 12:59 ` bot+bpf-ci
2026-05-27 11:39 ` [PATCHv6 bpf-next 23/29] selftests/bpf: Add tracing multi intersect tests Jiri Olsa
` (6 subsequent siblings)
28 siblings, 1 reply; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for tracing_multi link attachment via all possible
libbpf apis - skeleton, function pattern and btf ids on top of
bpf_testmod kernel module.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/testing/selftests/bpf/Makefile | 4 +-
.../selftests/bpf/prog_tests/tracing_multi.c | 105 ++++++++++++++++++
.../bpf/progs/tracing_multi_attach_module.c | 25 +++++
.../selftests/bpf/progs/tracing_multi_check.c | 50 +++++++++
4 files changed, 183 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_attach_module.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 396b68f862fe..fcfeb0aeff11 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -500,7 +500,8 @@ SKEL_BLACKLIST := btf__% test_pinning_invalid.c test_sk_assign.c
LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \
linked_vars.skel.h linked_maps.skel.h \
test_subskeleton.skel.h test_subskeleton_lib.skel.h \
- test_usdt.skel.h tracing_multi.skel.h
+ test_usdt.skel.h tracing_multi.skel.h \
+ tracing_multi_module.skel.h
LSKELS := fexit_sleep.c trace_printk.c trace_vprintk.c map_ptr_kern.c \
core_kern.c core_kern_overflow.c test_ringbuf.c \
@@ -527,6 +528,7 @@ xsk_xdp_progs.skel.h-deps := xsk_xdp_progs.bpf.o
xdp_hw_metadata.skel.h-deps := xdp_hw_metadata.bpf.o
xdp_features.skel.h-deps := xdp_features.bpf.o
tracing_multi.skel.h-deps := tracing_multi_attach.bpf.o tracing_multi_check.bpf.o
+tracing_multi_module.skel.h-deps := tracing_multi_attach_module.bpf.o tracing_multi_check.bpf.o
LINKED_BPF_OBJS := $(foreach skel,$(LINKED_SKELS),$($(skel)-deps))
LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.c,$(LINKED_BPF_OBJS))
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index e290513358d9..746a8398211a 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -5,6 +5,7 @@
#include <search.h>
#include "bpf/libbpf_internal.h"
#include "tracing_multi.skel.h"
+#include "tracing_multi_module.skel.h"
#include "trace_helpers.h"
static const char * const bpf_fentry_test[] = {
@@ -20,6 +21,14 @@ static const char * const bpf_fentry_test[] = {
"bpf_fentry_test10",
};
+static const char * const bpf_testmod_fentry_test[] = {
+ "bpf_testmod_fentry_test1",
+ "bpf_testmod_fentry_test2",
+ "bpf_testmod_fentry_test3",
+ "bpf_testmod_fentry_test7",
+ "bpf_testmod_fentry_test11",
+};
+
#define FUNCS_CNT (ARRAY_SIZE(bpf_fentry_test))
static int compare(const void *ppa, const void *ppb)
@@ -241,6 +250,96 @@ static void test_link_api_ids(void)
free(ids);
}
+static void test_module_skel_api(void)
+{
+ struct tracing_multi_module *skel = NULL;
+ int err;
+
+ skel = tracing_multi_module__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ err = tracing_multi_module__attach(skel);
+ if (!ASSERT_OK(err, "tracing_multi__attach"))
+ goto cleanup;
+
+ ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+ ASSERT_EQ(skel->bss->test_result_fentry, 5, "test_result_fentry");
+ ASSERT_EQ(skel->bss->test_result_fexit, 5, "test_result_fexit");
+
+cleanup:
+ tracing_multi_module__destroy(skel);
+}
+
+static void test_module_link_api_pattern(void)
+{
+ struct tracing_multi_module *skel = NULL;
+
+ skel = tracing_multi_module__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_module__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ "bpf_testmod:bpf_testmod_fentry_test*", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ "bpf_testmod:bpf_testmod_fentry_test*", NULL);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+ ASSERT_EQ(skel->bss->test_result_fentry, 5, "test_result_fentry");
+ ASSERT_EQ(skel->bss->test_result_fexit, 5, "test_result_fexit");
+
+cleanup:
+ tracing_multi_module__destroy(skel);
+}
+
+static void test_module_link_api_ids(void)
+{
+ size_t cnt = ARRAY_SIZE(bpf_testmod_fentry_test);
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi_module *skel = NULL;
+ __u32 *ids;
+
+ skel = tracing_multi_module__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_module__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ ids = get_ids(bpf_testmod_fentry_test, cnt, "bpf_testmod");
+ if (!ASSERT_OK_PTR(ids, "get_ids"))
+ goto cleanup;
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ NULL, &opts);
+ if (!ASSERT_OK_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+ ASSERT_EQ(skel->bss->test_result_fentry, 5, "test_result_fentry");
+ ASSERT_EQ(skel->bss->test_result_fexit, 5, "test_result_fexit");
+
+cleanup:
+ tracing_multi_module__destroy(skel);
+ free(ids);
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
@@ -254,4 +353,10 @@ void test_tracing_multi_test(void)
test_link_api_pattern();
if (test__start_subtest("link_api_ids"))
test_link_api_ids();
+ if (test__start_subtest("module_skel_api"))
+ test_module_skel_api();
+ if (test__start_subtest("module_link_api_pattern"))
+ test_module_link_api_pattern();
+ if (test__start_subtest("module_link_api_ids"))
+ test_module_link_api_ids();
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_attach_module.c b/tools/testing/selftests/bpf/progs/tracing_multi_attach_module.c
new file mode 100644
index 000000000000..b3374f2db450
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_attach_module.c
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__hidden extern int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return);
+
+__u64 test_result_fentry = 0;
+__u64 test_result_fexit = 0;
+
+SEC("fentry.multi/bpf_testmod:bpf_testmod_fentry_test*")
+int BPF_PROG(test_fentry)
+{
+ tracing_multi_arg_check(ctx, &test_result_fentry, false);
+ return 0;
+}
+
+SEC("fexit.multi/bpf_testmod:bpf_testmod_fentry_test*")
+int BPF_PROG(test_fexit)
+{
+ tracing_multi_arg_check(ctx, &test_result_fexit, true);
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_check.c b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
index 333a3a7bae8a..7ede84c50cb6 100644
--- a/tools/testing/selftests/bpf/progs/tracing_multi_check.c
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
@@ -18,6 +18,12 @@ extern const void bpf_fentry_test8 __ksym;
extern const void bpf_fentry_test9 __ksym;
extern const void bpf_fentry_test10 __ksym;
+extern const void bpf_testmod_fentry_test1 __ksym;
+extern const void bpf_testmod_fentry_test2 __ksym;
+extern const void bpf_testmod_fentry_test3 __ksym;
+extern const void bpf_testmod_fentry_test7 __ksym;
+extern const void bpf_testmod_fentry_test11 __ksym;
+
int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
{
void *ip = (void *) bpf_get_func_ip(ctx);
@@ -145,6 +151,50 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
err |= is_return ? ret != 0 : 0;
*test_result += err == 0 ? 1 : 0;
+ } else if (ip == &bpf_testmod_fentry_test1) {
+ int a;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (int) value;
+
+ err |= is_return ? ret != 2 : 0;
+
+ *test_result += err == 0 && a == 1;
+ } else if (ip == &bpf_testmod_fentry_test2) {
+ int a;
+ __u64 b;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (int) value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (__u64) value;
+
+ err |= is_return ? ret != 5 : 0;
+
+ *test_result += err == 0 && a == 2 && b == 3;
+ } else if (ip == &bpf_testmod_fentry_test3) {
+ char a;
+ int b;
+ __u64 c;
+
+ err |= bpf_get_func_arg(ctx, 0, &value);
+ a = (char) value;
+ err |= bpf_get_func_arg(ctx, 1, &value);
+ b = (int) value;
+ err |= bpf_get_func_arg(ctx, 2, &value);
+ c = (__u64) value;
+
+ err |= is_return ? ret != 15 : 0;
+
+ *test_result += err == 0 && a == 4 && b == 5 && c == 6;
+ } else if (ip == &bpf_testmod_fentry_test7) {
+ err |= is_return ? ret != 133 : 0;
+
+ *test_result += err == 0;
+ } else if (ip == &bpf_testmod_fentry_test11) {
+ err |= is_return ? ret != 231 : 0;
+
+ *test_result += err == 0;
}
return 0;
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* Re: [PATCHv6 bpf-next 22/29] selftests/bpf: Add tracing multi skel/pattern/ids module attach tests
2026-05-27 11:39 ` [PATCHv6 bpf-next 22/29] selftests/bpf: Add tracing multi skel/pattern/ids module " Jiri Olsa
@ 2026-05-27 12:59 ` bot+bpf-ci
0 siblings, 0 replies; 34+ messages in thread
From: bot+bpf-ci @ 2026-05-27 12:59 UTC (permalink / raw)
To: jolsa, ast, daniel, andrii
Cc: bpf, linux-trace-kernel, kafai, eddyz87, songliubraving, yhs,
menglong8.dong, rostedt, ast, andrii, daniel, martin.lau, eddyz87,
yonghong.song, clm, ihor.solodrai
[-- Attachment #1: Type: text/plain, Size: 2238 bytes --]
> diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> index e290513358d9..746a8398211a 100644
> --- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
> +++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
[ ... ]
> @@ -241,6 +250,96 @@ static void test_link_api_ids(void)
[ ... ]
> +static void test_module_link_api_ids(void)
> +{
> + size_t cnt = ARRAY_SIZE(bpf_testmod_fentry_test);
> + LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
> + struct tracing_multi_module *skel = NULL;
> + __u32 *ids;
> +
> + skel = tracing_multi_module__open_and_load();
> + if (!ASSERT_OK_PTR(skel, "tracing_multi_module__open_and_load"))
> + return;
> +
> + skel->bss->pid = getpid();
> +
> + ids = get_ids(bpf_testmod_fentry_test, cnt, "bpf_testmod");
> + if (!ASSERT_OK_PTR(ids, "get_ids"))
> + goto cleanup;
This new test calls get_ids() but there's an unaddressed review comment
from sashiko-bot about a memory leak in that function. Looking at get_ids()
in the same file:
for (i = 0; i < funcs_cnt; i++) {
if (!tsearch(&funcs[i], &root, compare)) {
ASSERT_FAIL("tsearch failed");
err = -1;
goto out;
}
}
...
if (err) {
free(ids);
ids = NULL;
}
out:
tdestroy(root, tdestroy_free_nop);
btf__free(vmlinux_btf);
btf__free(btf);
return ids;
If tsearch() fails, the code sets err = -1 and jumps to the out label.
However, the out label is positioned after the cleanup block that frees ids
(the "if (err)" block), not before it. This means the cleanup code is
bypassed when we goto out, causing two issues:
1. The ids array is leaked
2. The function returns a non-NULL pointer to allocated but potentially
invalid memory, which will incorrectly pass the ASSERT_OK_PTR check above
Should the out label be moved before the cleanup block so that the error
path properly frees the ids array and sets it to NULL?
---
AI reviewed your patch. Please fix the bug or email reply why it's not a bug.
See: https://github.com/kernel-patches/vmtest/blob/master/ci/claude/README.md
CI run summary: https://github.com/kernel-patches/bpf/actions/runs/26509800686
^ permalink raw reply [flat|nested] 34+ messages in thread
* [PATCHv6 bpf-next 23/29] selftests/bpf: Add tracing multi intersect tests
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (21 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 22/29] selftests/bpf: Add tracing multi skel/pattern/ids module " Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 24/29] selftests/bpf: Add tracing multi cookies test Jiri Olsa
` (5 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tracing multi tests for intersecting attached functions.
Using bits from (from 1 to 16 values) to specify (up to 4) attached
programs, and randomly choosing bpf_fentry_test* functions they are
attached to.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/testing/selftests/bpf/Makefile | 4 +-
.../selftests/bpf/prog_tests/tracing_multi.c | 99 +++++++++++++++++++
.../progs/tracing_multi_intersect_attach.c | 41 ++++++++
3 files changed, 143 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index fcfeb0aeff11..95b87cba46bc 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -501,7 +501,8 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \
linked_vars.skel.h linked_maps.skel.h \
test_subskeleton.skel.h test_subskeleton_lib.skel.h \
test_usdt.skel.h tracing_multi.skel.h \
- tracing_multi_module.skel.h
+ tracing_multi_module.skel.h \
+ tracing_multi_intersect.skel.h
LSKELS := fexit_sleep.c trace_printk.c trace_vprintk.c map_ptr_kern.c \
core_kern.c core_kern_overflow.c test_ringbuf.c \
@@ -529,6 +530,7 @@ xdp_hw_metadata.skel.h-deps := xdp_hw_metadata.bpf.o
xdp_features.skel.h-deps := xdp_features.bpf.o
tracing_multi.skel.h-deps := tracing_multi_attach.bpf.o tracing_multi_check.bpf.o
tracing_multi_module.skel.h-deps := tracing_multi_attach_module.bpf.o tracing_multi_check.bpf.o
+tracing_multi_intersect.skel.h-deps := tracing_multi_intersect_attach.bpf.o tracing_multi_check.bpf.o
LINKED_BPF_OBJS := $(foreach skel,$(LINKED_SKELS),$($(skel)-deps))
LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.c,$(LINKED_BPF_OBJS))
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index 746a8398211a..26acc1a480cf 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -6,6 +6,7 @@
#include "bpf/libbpf_internal.h"
#include "tracing_multi.skel.h"
#include "tracing_multi_module.skel.h"
+#include "tracing_multi_intersect.skel.h"
#include "trace_helpers.h"
static const char * const bpf_fentry_test[] = {
@@ -31,6 +32,20 @@ static const char * const bpf_testmod_fentry_test[] = {
#define FUNCS_CNT (ARRAY_SIZE(bpf_fentry_test))
+static int get_random_funcs(const char **funcs)
+{
+ int i, cnt = 0;
+
+ for (i = 0; i < FUNCS_CNT; i++) {
+ if (rand() % 2)
+ funcs[cnt++] = bpf_fentry_test[i];
+ }
+ /* we always need at least one.. */
+ if (!cnt)
+ funcs[cnt++] = bpf_fentry_test[rand() % FUNCS_CNT];
+ return cnt;
+}
+
static int compare(const void *ppa, const void *ppb)
{
const char *pa = *(const char **) ppa;
@@ -340,6 +355,88 @@ static void test_module_link_api_ids(void)
free(ids);
}
+static bool is_set(__u32 mask, __u32 bit)
+{
+ return (1 << bit) & mask;
+}
+
+static void __test_intersect(__u32 mask, const struct bpf_program *progs[4], __u64 *test_results[4])
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ LIBBPF_OPTS(bpf_test_run_opts, topts);
+ struct bpf_link *links[4] = { NULL };
+ const char *funcs[FUNCS_CNT];
+ __u64 expected[4];
+ __u32 *ids, i;
+ int err, cnt;
+
+ /*
+ * We have 4 programs in progs and the mask bits pick which
+ * of them gets attached to randomly chosen functions.
+ */
+ for (i = 0; i < 4; i++) {
+ if (!is_set(mask, i))
+ continue;
+
+ cnt = get_random_funcs(funcs);
+ ids = get_ids(funcs, cnt, NULL);
+ if (!ASSERT_OK_PTR(ids, "get_ids"))
+ goto cleanup;
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+ links[i] = bpf_program__attach_tracing_multi(progs[i], NULL, &opts);
+ free(ids);
+
+ if (!ASSERT_OK_PTR(links[i], "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ expected[i] = *test_results[i] + cnt;
+ }
+
+ err = bpf_prog_test_run_opts(bpf_program__fd(progs[0]), &topts);
+ ASSERT_OK(err, "test_run");
+
+ for (i = 0; i < 4; i++) {
+ if (!is_set(mask, i))
+ continue;
+ ASSERT_EQ(*test_results[i], expected[i], "test_results");
+ }
+
+cleanup:
+ for (i = 0; i < 4; i++)
+ bpf_link__destroy(links[i]);
+}
+
+static void test_intersect(void)
+{
+ struct tracing_multi_intersect *skel;
+ const struct bpf_program *progs[4];
+ __u64 *test_results[4];
+ __u32 i;
+
+ skel = tracing_multi_intersect__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_intersect__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ progs[0] = skel->progs.fentry_1;
+ progs[1] = skel->progs.fexit_1;
+ progs[2] = skel->progs.fentry_2;
+ progs[3] = skel->progs.fexit_2;
+
+ test_results[0] = &skel->bss->test_result_fentry_1;
+ test_results[1] = &skel->bss->test_result_fexit_1;
+ test_results[2] = &skel->bss->test_result_fentry_2;
+ test_results[3] = &skel->bss->test_result_fexit_2;
+
+ for (i = 1; i < 16; i++)
+ __test_intersect(i, progs, test_results);
+
+ tracing_multi_intersect__destroy(skel);
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
@@ -359,4 +456,6 @@ void test_tracing_multi_test(void)
test_module_link_api_pattern();
if (test__start_subtest("module_link_api_ids"))
test_module_link_api_ids();
+ if (test__start_subtest("intersect"))
+ test_intersect();
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c b/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c
new file mode 100644
index 000000000000..cd5be0bb6ffd
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_intersect_attach.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__hidden extern int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return);
+
+__u64 test_result_fentry_1 = 0;
+__u64 test_result_fentry_2 = 0;
+__u64 test_result_fexit_1 = 0;
+__u64 test_result_fexit_2 = 0;
+
+SEC("fentry.multi")
+int BPF_PROG(fentry_1)
+{
+ tracing_multi_arg_check(ctx, &test_result_fentry_1, false);
+ return 0;
+}
+
+SEC("fentry.multi")
+int BPF_PROG(fentry_2)
+{
+ tracing_multi_arg_check(ctx, &test_result_fentry_2, false);
+ return 0;
+}
+
+SEC("fexit.multi")
+int BPF_PROG(fexit_1)
+{
+ tracing_multi_arg_check(ctx, &test_result_fexit_1, true);
+ return 0;
+}
+
+SEC("fexit.multi")
+int BPF_PROG(fexit_2)
+{
+ tracing_multi_arg_check(ctx, &test_result_fexit_2, true);
+ return 0;
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 24/29] selftests/bpf: Add tracing multi cookies test
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (22 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 23/29] selftests/bpf: Add tracing multi intersect tests Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 25/29] selftests/bpf: Add tracing multi session test Jiri Olsa
` (4 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for using cookies on tracing multi link.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/tracing_multi.c | 23 +++++++++++++++++--
.../selftests/bpf/progs/tracing_multi_check.c | 15 +++++++++++-
2 files changed, 35 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index 26acc1a480cf..f27c086d3f78 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -9,6 +9,19 @@
#include "tracing_multi_intersect.skel.h"
#include "trace_helpers.h"
+static __u64 bpf_fentry_test_cookies[] = {
+ 8, /* bpf_fentry_test1 */
+ 9, /* bpf_fentry_test2 */
+ 7, /* bpf_fentry_test3 */
+ 5, /* bpf_fentry_test4 */
+ 4, /* bpf_fentry_test5 */
+ 2, /* bpf_fentry_test6 */
+ 3, /* bpf_fentry_test7 */
+ 1, /* bpf_fentry_test8 */
+ 10, /* bpf_fentry_test9 */
+ 6, /* bpf_fentry_test10 */
+};
+
static const char * const bpf_fentry_test[] = {
"bpf_fentry_test1",
"bpf_fentry_test2",
@@ -216,7 +229,7 @@ static void test_link_api_pattern(void)
tracing_multi__destroy(skel);
}
-static void test_link_api_ids(void)
+static void test_link_api_ids(bool test_cookies)
{
LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
struct tracing_multi *skel;
@@ -228,6 +241,7 @@ static void test_link_api_ids(void)
return;
skel->bss->pid = getpid();
+ skel->bss->test_cookies = test_cookies;
ids = get_ids(bpf_fentry_test, cnt, NULL);
if (!ASSERT_OK_PTR(ids, "get_ids"))
@@ -236,6 +250,9 @@ static void test_link_api_ids(void)
opts.ids = ids;
opts.cnt = cnt;
+ if (test_cookies)
+ opts.cookies = bpf_fentry_test_cookies;
+
skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
NULL, &opts);
if (!ASSERT_OK_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
@@ -449,7 +466,7 @@ void test_tracing_multi_test(void)
if (test__start_subtest("link_api_pattern"))
test_link_api_pattern();
if (test__start_subtest("link_api_ids"))
- test_link_api_ids();
+ test_link_api_ids(false);
if (test__start_subtest("module_skel_api"))
test_module_skel_api();
if (test__start_subtest("module_link_api_pattern"))
@@ -458,4 +475,6 @@ void test_tracing_multi_test(void)
test_module_link_api_ids();
if (test__start_subtest("intersect"))
test_intersect();
+ if (test__start_subtest("cookies"))
+ test_link_api_ids(true);
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_check.c b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
index 7ede84c50cb6..b2959ba71179 100644
--- a/tools/testing/selftests/bpf/progs/tracing_multi_check.c
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_check.c
@@ -6,6 +6,7 @@
char _license[] SEC("license") = "GPL";
int pid = 0;
+bool test_cookies = false;
/* bpf_fentry_test1 is exported as kfunc via vmlinux.h */
extern const void bpf_fentry_test2 __ksym;
@@ -27,7 +28,7 @@ extern const void bpf_testmod_fentry_test11 __ksym;
int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
{
void *ip = (void *) bpf_get_func_ip(ctx);
- __u64 value = 0, ret = 0;
+ __u64 value = 0, ret = 0, cookie = 0;
long err = 0;
if (bpf_get_current_pid_tgid() >> 32 != pid)
@@ -35,6 +36,8 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
if (is_return)
err |= bpf_get_func_ret(ctx, &ret);
+ if (test_cookies)
+ cookie = bpf_get_attach_cookie(ctx);
if (ip == &bpf_fentry_test1) {
int a;
@@ -43,6 +46,7 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
a = (int) value;
err |= is_return ? ret != 2 : 0;
+ err |= test_cookies ? cookie != 8 : 0;
*test_result += err == 0 && a == 1;
} else if (ip == &bpf_fentry_test2) {
@@ -55,6 +59,7 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
b = value;
err |= is_return ? ret != 5 : 0;
+ err |= test_cookies ? cookie != 9 : 0;
*test_result += err == 0 && a == 2 && b == 3;
} else if (ip == &bpf_fentry_test3) {
@@ -70,6 +75,7 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
c = value;
err |= is_return ? ret != 15 : 0;
+ err |= test_cookies ? cookie != 7 : 0;
*test_result += err == 0 && a == 4 && b == 5 && c == 6;
} else if (ip == &bpf_fentry_test4) {
@@ -88,6 +94,7 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
d = value;
err |= is_return ? ret != 34 : 0;
+ err |= test_cookies ? cookie != 5 : 0;
*test_result += err == 0 && a == (void *) 7 && b == 8 && c == 9 && d == 10;
} else if (ip == &bpf_fentry_test5) {
@@ -109,6 +116,7 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
e = value;
err |= is_return ? ret != 65 : 0;
+ err |= test_cookies ? cookie != 4 : 0;
*test_result += err == 0 && a == 11 && b == (void *) 12 && c == 13 && d == 14 && e == 15;
} else if (ip == &bpf_fentry_test6) {
@@ -133,22 +141,27 @@ int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return)
f = value;
err |= is_return ? ret != 111 : 0;
+ err |= test_cookies ? cookie != 2 : 0;
*test_result += err == 0 && a == 16 && b == (void *) 17 && c == 18 && d == 19 && e == (void *) 20 && f == 21;
} else if (ip == &bpf_fentry_test7) {
err |= is_return ? ret != 0 : 0;
+ err |= test_cookies ? cookie != 3 : 0;
*test_result += err == 0 ? 1 : 0;
} else if (ip == &bpf_fentry_test8) {
err |= is_return ? ret != 0 : 0;
+ err |= test_cookies ? cookie != 1 : 0;
*test_result += err == 0 ? 1 : 0;
} else if (ip == &bpf_fentry_test9) {
err |= is_return ? ret != 0 : 0;
+ err |= test_cookies ? cookie != 10 : 0;
*test_result += err == 0 ? 1 : 0;
} else if (ip == &bpf_fentry_test10) {
err |= is_return ? ret != 0 : 0;
+ err |= test_cookies ? cookie != 6 : 0;
*test_result += err == 0 ? 1 : 0;
} else if (ip == &bpf_testmod_fentry_test1) {
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 25/29] selftests/bpf: Add tracing multi session test
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (23 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 24/29] selftests/bpf: Add tracing multi cookies test Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 26/29] selftests/bpf: Add tracing multi attach fails test Jiri Olsa
` (3 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for tracing multi link session.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
tools/testing/selftests/bpf/Makefile | 4 +-
.../selftests/bpf/prog_tests/tracing_multi.c | 40 ++++++++++++++++
.../bpf/progs/tracing_multi_session_attach.c | 47 +++++++++++++++++++
3 files changed, 90 insertions(+), 1 deletion(-)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_session_attach.c
diff --git a/tools/testing/selftests/bpf/Makefile b/tools/testing/selftests/bpf/Makefile
index 95b87cba46bc..30ad24bb7054 100644
--- a/tools/testing/selftests/bpf/Makefile
+++ b/tools/testing/selftests/bpf/Makefile
@@ -502,7 +502,8 @@ LINKED_SKELS := test_static_linked.skel.h linked_funcs.skel.h \
test_subskeleton.skel.h test_subskeleton_lib.skel.h \
test_usdt.skel.h tracing_multi.skel.h \
tracing_multi_module.skel.h \
- tracing_multi_intersect.skel.h
+ tracing_multi_intersect.skel.h \
+ tracing_multi_session.skel.h
LSKELS := fexit_sleep.c trace_printk.c trace_vprintk.c map_ptr_kern.c \
core_kern.c core_kern_overflow.c test_ringbuf.c \
@@ -531,6 +532,7 @@ xdp_features.skel.h-deps := xdp_features.bpf.o
tracing_multi.skel.h-deps := tracing_multi_attach.bpf.o tracing_multi_check.bpf.o
tracing_multi_module.skel.h-deps := tracing_multi_attach_module.bpf.o tracing_multi_check.bpf.o
tracing_multi_intersect.skel.h-deps := tracing_multi_intersect_attach.bpf.o tracing_multi_check.bpf.o
+tracing_multi_session.skel.h-deps := tracing_multi_session_attach.bpf.o tracing_multi_check.bpf.o
LINKED_BPF_OBJS := $(foreach skel,$(LINKED_SKELS),$($(skel)-deps))
LINKED_BPF_SRCS := $(patsubst %.bpf.o,%.c,$(LINKED_BPF_OBJS))
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index f27c086d3f78..202005f2dbeb 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -7,6 +7,7 @@
#include "tracing_multi.skel.h"
#include "tracing_multi_module.skel.h"
#include "tracing_multi_intersect.skel.h"
+#include "tracing_multi_session.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -454,6 +455,43 @@ static void test_intersect(void)
tracing_multi_intersect__destroy(skel);
}
+static void test_session(void)
+{
+ LIBBPF_OPTS(bpf_test_run_opts, topts);
+ struct tracing_multi_session *skel;
+ int err, prog_fd;
+
+ skel = tracing_multi_session__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_session__open_and_load"))
+ return;
+
+ skel->bss->pid = getpid();
+
+ err = tracing_multi_session__attach(skel);
+ if (!ASSERT_OK(err, "tracing_multi_session__attach"))
+ goto cleanup;
+
+ /* execute kernel session */
+ prog_fd = bpf_program__fd(skel->progs.test_session_1);
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run");
+
+ ASSERT_EQ(skel->bss->test_result_fentry, 10, "test_result_fentry");
+ /* extra count (+1 for each fexit execution) for test_result_fexit cookie */
+ ASSERT_EQ(skel->bss->test_result_fexit, 20, "test_result_fexit");
+
+ /* execute bpf_testmo.ko session */
+ ASSERT_OK(trigger_module_test_read(1), "trigger_read");
+
+ ASSERT_EQ(skel->bss->test_result_fentry, 15, "test_result_fentry");
+ /* extra count (+1 for each fexit execution) for test_result_fexit cookie */
+ ASSERT_EQ(skel->bss->test_result_fexit, 30, "test_result_fexit");
+
+
+cleanup:
+ tracing_multi_session__destroy(skel);
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
@@ -477,4 +515,6 @@ void test_tracing_multi_test(void)
test_intersect();
if (test__start_subtest("cookies"))
test_link_api_ids(true);
+ if (test__start_subtest("session"))
+ test_session();
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_session_attach.c b/tools/testing/selftests/bpf/progs/tracing_multi_session_attach.c
new file mode 100644
index 000000000000..4dc9bce96097
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_session_attach.c
@@ -0,0 +1,47 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+__hidden extern int tracing_multi_arg_check(__u64 *ctx, __u64 *test_result, bool is_return);
+
+__u64 test_result_fentry = 0;
+__u64 test_result_fexit = 0;
+
+SEC("fsession.multi/bpf_fentry_test*")
+int BPF_PROG(test_session_1)
+{
+ volatile __u64 *cookie = bpf_session_cookie(ctx);
+
+ if (bpf_session_is_return(ctx)) {
+ if (tracing_multi_arg_check(ctx, &test_result_fexit, true))
+ return 0;
+ /* extra count for test_result_fexit cookie */
+ test_result_fexit += *cookie == 0xbeafbeafbeafbeaf;
+ } else {
+ if (tracing_multi_arg_check(ctx, &test_result_fentry, false))
+ return 0;
+ *cookie = 0xbeafbeafbeafbeaf;
+ }
+ return 0;
+}
+
+SEC("fsession.multi/bpf_testmod:bpf_testmod_fentry_test*")
+int BPF_PROG(test_session_2)
+{
+ volatile __u64 *cookie = bpf_session_cookie(ctx);
+
+ if (bpf_session_is_return(ctx)) {
+ if (tracing_multi_arg_check(ctx, &test_result_fexit, true))
+ return 0;
+ /* extra count for test_result_fexit cookie */
+ test_result_fexit += *cookie == 0xbeafbeafbeafbeaf;
+ } else {
+ if (tracing_multi_arg_check(ctx, &test_result_fentry, false))
+ return 0;
+ *cookie = 0xbeafbeafbeafbeaf;
+ }
+ return 0;
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 26/29] selftests/bpf: Add tracing multi attach fails test
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (24 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 25/29] selftests/bpf: Add tracing multi session test Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 27/29] selftests/bpf: Add tracing multi verifier " Jiri Olsa
` (2 subsequent siblings)
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for attach fails on tracing multi link.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/tracing_multi.c | 96 +++++++++++++++++++
.../selftests/bpf/progs/tracing_multi_fail.c | 18 ++++
2 files changed, 114 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_fail.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index 202005f2dbeb..f968dcabd795 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -8,6 +8,7 @@
#include "tracing_multi_module.skel.h"
#include "tracing_multi_intersect.skel.h"
#include "tracing_multi_session.skel.h"
+#include "tracing_multi_fail.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -492,6 +493,99 @@ static void test_session(void)
tracing_multi_session__destroy(skel);
}
+static void test_attach_api_fails(void)
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ static const char * const func[] = {
+ "bpf_fentry_test2",
+ };
+ struct tracing_multi_fail *skel = NULL;
+ __u32 ids[2] = {}, *ids2 = NULL;
+ __u64 cookies[2];
+
+ skel = tracing_multi_fail__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_fail__open_and_load"))
+ return;
+
+ /* fail#1 (libbpf) pattern and opts NULL */
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, NULL);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -EINVAL, "fail_1"))
+ goto cleanup;
+
+ /* fail#2 (libbpf) pattern and ids */
+ LIBBPF_OPTS_RESET(opts,
+ .ids = ids,
+ .cnt = 2,
+ );
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ "bpf_fentry_test*", &opts);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -EINVAL, "fail_2"))
+ goto cleanup;
+
+ /* fail#3 (libbpf) pattern and cookies */
+ LIBBPF_OPTS_RESET(opts,
+ .ids = NULL,
+ .cnt = 2,
+ .cookies = cookies,
+ );
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ "bpf_fentry_test*", &opts);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -EINVAL, "fail_3"))
+ goto cleanup;
+
+ /* fail#4 (libbpf) bogus pattern */
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ "bpf_not_really_a_function*", NULL);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -EINVAL, "fail_4"))
+ goto cleanup;
+
+ /* fail#5 (kernel) abnormal cnt */
+ LIBBPF_OPTS_RESET(opts,
+ .ids = ids,
+ .cnt = INT_MAX,
+ );
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -E2BIG, "fail_5"))
+ goto cleanup;
+
+ /* fail#6 (kernel) attach sleepable program to not-allowed function */
+ ids2 = get_ids(func, 1, NULL);
+ if (!ASSERT_OK_PTR(ids2, "get_ids"))
+ goto cleanup;
+
+ LIBBPF_OPTS_RESET(opts,
+ .ids = ids2,
+ .cnt = 1,
+ );
+
+ skel->links.test_fentry_s = bpf_program__attach_tracing_multi(skel->progs.test_fentry_s,
+ NULL, &opts);
+ if (!ASSERT_EQ(libbpf_get_error(skel->links.test_fentry_s), -EINVAL, "fail_6"))
+ goto cleanup;
+
+ /* fail#7 (kernel) attach with duplicate id */
+ ids[0] = ids2[0];
+ ids[1] = ids2[0];
+
+ LIBBPF_OPTS_RESET(opts,
+ .ids = ids,
+ .cnt = 2,
+ );
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ ASSERT_EQ(libbpf_get_error(skel->links.test_fentry), -EINVAL, "fail_7");
+
+cleanup:
+ tracing_multi_fail__destroy(skel);
+ free(ids2);
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
@@ -517,4 +611,6 @@ void test_tracing_multi_test(void)
test_link_api_ids(true);
if (test__start_subtest("session"))
test_session();
+ if (test__start_subtest("attach_api_fails"))
+ test_attach_api_fails();
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_fail.c b/tools/testing/selftests/bpf/progs/tracing_multi_fail.c
new file mode 100644
index 000000000000..7f0375f4213d
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_fail.c
@@ -0,0 +1,18 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+SEC("fentry.multi")
+int BPF_PROG(test_fentry)
+{
+ return 0;
+}
+
+SEC("fentry.multi.s")
+int BPF_PROG(test_fentry_s)
+{
+ return 0;
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 27/29] selftests/bpf: Add tracing multi verifier fails test
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (25 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 26/29] selftests/bpf: Add tracing multi attach fails test Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 28/29] selftests/bpf: Add tracing multi attach benchmark test Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 29/29] selftests/bpf: Add tracing multi attach rollback tests Jiri Olsa
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for verifier fails on tracing multi programs.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/tracing_multi.c | 2 ++
.../bpf/progs/tracing_multi_verifier.c | 31 +++++++++++++++++++
2 files changed, 33 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_verifier.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index f968dcabd795..43401e93b778 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -9,6 +9,7 @@
#include "tracing_multi_intersect.skel.h"
#include "tracing_multi_session.skel.h"
#include "tracing_multi_fail.skel.h"
+#include "tracing_multi_verifier.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -613,4 +614,5 @@ void test_tracing_multi_test(void)
test_session();
if (test__start_subtest("attach_api_fails"))
test_attach_api_fails();
+ RUN_TESTS(tracing_multi_verifier);
}
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_verifier.c b/tools/testing/selftests/bpf/progs/tracing_multi_verifier.c
new file mode 100644
index 000000000000..7b6ed41bf452
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_verifier.c
@@ -0,0 +1,31 @@
+// SPDX-License-Identifier: GPL-2.0
+#include "vmlinux.h"
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+#include "bpf_misc.h"
+
+char _license[] SEC("license") = "GPL";
+
+SEC("fentry.multi/bpf_fentry_test1")
+__failure
+__msg("func 'bpf_multi_func' doesn't have 1-th argument")
+int BPF_PROG(fentry_direct_access, int a)
+{
+ return a;
+}
+
+SEC("fexit.multi/bpf_fentry_test3")
+__failure
+__msg("invalid bpf_context access off=24 size=8")
+int BPF_PROG(fexit_direct_access, char a, int b, __u64 c, int ret)
+{
+ return ret;
+}
+
+SEC("fsession.multi/bpf_fentry_test4")
+__failure
+__msg("invalid bpf_context access off=16 size=8")
+int BPF_PROG(fsession_direct_access, void *a, char b, int c, __u64 d, int ret)
+{
+ return c;
+}
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 28/29] selftests/bpf: Add tracing multi attach benchmark test
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (26 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 27/29] selftests/bpf: Add tracing multi verifier " Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
2026-05-27 11:39 ` [PATCHv6 bpf-next 29/29] selftests/bpf: Add tracing multi attach rollback tests Jiri Olsa
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding benchmark test that attaches to (almost) all allowed tracing
functions and display attach/detach times.
# ./test_progs -t tracing_multi_bench_attach -v
bpf_testmod.ko is already unloaded.
Loading bpf_testmod.ko...
Successfully loaded bpf_testmod.ko.
serial_test_tracing_multi_bench_attach:PASS:btf__load_vmlinux_btf 0 nsec
serial_test_tracing_multi_bench_attach:PASS:tracing_multi_bench__open_and_load 0 nsec
serial_test_tracing_multi_bench_attach:PASS:get_syms 0 nsec
serial_test_tracing_multi_bench_attach:PASS:bpf_program__attach_tracing_multi 0 nsec
serial_test_tracing_multi_bench_attach: found 51186 functions
serial_test_tracing_multi_bench_attach: attached in 1.295s
serial_test_tracing_multi_bench_attach: detached in 0.243s
#507 tracing_multi_bench_attach:OK
Summary: 1/0 PASSED, 0 SKIPPED, 0 FAILED
Successfully unloaded bpf_testmod.ko.
Exporting skip_entry as is_unsafe_function and using it in the test.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/tracing_multi.c | 100 ++++++++++++++++++
.../selftests/bpf/progs/tracing_multi_bench.c | 12 +++
tools/testing/selftests/bpf/trace_helpers.c | 6 +-
tools/testing/selftests/bpf/trace_helpers.h | 1 +
4 files changed, 116 insertions(+), 3 deletions(-)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_bench.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index 43401e93b778..e437e6cec222 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -10,6 +10,7 @@
#include "tracing_multi_session.skel.h"
#include "tracing_multi_fail.skel.h"
#include "tracing_multi_verifier.skel.h"
+#include "tracing_multi_bench.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -587,6 +588,105 @@ static void test_attach_api_fails(void)
free(ids2);
}
+void serial_test_tracing_multi_bench_attach(void)
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi_bench *skel = NULL;
+ long attach_start_ns, attach_end_ns;
+ long detach_start_ns, detach_end_ns;
+ double attach_delta, detach_delta;
+ struct bpf_link *link = NULL;
+ size_t i, cap = 0, cnt = 0;
+ struct ksyms *ksyms = NULL;
+ void *root = NULL;
+ __u32 *ids = NULL;
+ __u32 nr, type_id;
+ struct btf *btf;
+ int err;
+
+#ifndef __x86_64__
+ test__skip();
+ return;
+#endif
+
+ btf = btf__load_vmlinux_btf();
+ if (!ASSERT_OK_PTR(btf, "btf__load_vmlinux_btf"))
+ return;
+
+ skel = tracing_multi_bench__open_and_load();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_bench__open_and_load"))
+ goto cleanup;
+
+ if (!ASSERT_OK(bpf_get_ksyms(&ksyms, true), "get_syms"))
+ goto cleanup;
+
+ /* Get all ftrace 'safe' symbols.. */
+ for (i = 0; i < ksyms->filtered_cnt; i++) {
+ if (!tsearch(&ksyms->filtered_syms[i], &root, compare)) {
+ ASSERT_FAIL("tsearch failed");
+ goto cleanup;
+ }
+ }
+
+ /* ..and filter them through BTF and btf_type_is_traceable_func. */
+ nr = btf__type_cnt(btf);
+ for (type_id = 1; type_id < nr; type_id++) {
+ const struct btf_type *type;
+ const char *str;
+
+ type = btf__type_by_id(btf, type_id);
+ if (!type)
+ break;
+
+ if (BTF_INFO_KIND(type->info) != BTF_KIND_FUNC)
+ continue;
+
+ str = btf__name_by_offset(btf, type->name_off);
+ if (!str)
+ break;
+
+ if (!tfind(&str, &root, compare))
+ continue;
+
+ if (!btf_type_is_traceable_func(btf, type))
+ continue;
+
+ err = libbpf_ensure_mem((void **) &ids, &cap, sizeof(*ids), cnt + 1);
+ if (err)
+ goto cleanup;
+
+ ids[cnt++] = type_id;
+ }
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ attach_start_ns = get_time_ns();
+ link = bpf_program__attach_tracing_multi(skel->progs.bench, NULL, &opts);
+ attach_end_ns = get_time_ns();
+
+ if (!ASSERT_OK_PTR(link, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ detach_start_ns = get_time_ns();
+ bpf_link__destroy(link);
+ detach_end_ns = get_time_ns();
+
+ attach_delta = (attach_end_ns - attach_start_ns) / 1000000000.0;
+ detach_delta = (detach_end_ns - detach_start_ns) / 1000000000.0;
+
+ printf("%s: found %lu functions\n", __func__, cnt);
+ printf("%s: attached in %7.3lfs\n", __func__, attach_delta);
+ printf("%s: detached in %7.3lfs\n", __func__, detach_delta);
+
+cleanup:
+ tracing_multi_bench__destroy(skel);
+ tdestroy(root, tdestroy_free_nop);
+ free_kallsyms_local(ksyms);
+ free(ids);
+ btf__free(btf);
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_bench.c b/tools/testing/selftests/bpf/progs/tracing_multi_bench.c
new file mode 100644
index 000000000000..beae946cb8c4
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_bench.c
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+SEC("fentry.multi")
+int BPF_PROG(bench)
+{
+ return 0;
+}
diff --git a/tools/testing/selftests/bpf/trace_helpers.c b/tools/testing/selftests/bpf/trace_helpers.c
index 0e63daf83ed5..8de0b60766de 100644
--- a/tools/testing/selftests/bpf/trace_helpers.c
+++ b/tools/testing/selftests/bpf/trace_helpers.c
@@ -548,7 +548,7 @@ static const char * const trace_blacklist[] = {
"bpf_get_numa_node_id",
};
-static bool skip_entry(char *name)
+bool is_unsafe_function(const char *name)
{
int i;
@@ -651,7 +651,7 @@ int bpf_get_ksyms(struct ksyms **ksymsp, bool kernel)
free(name);
if (sscanf(buf, "%ms$*[^\n]\n", &name) != 1)
continue;
- if (skip_entry(name))
+ if (is_unsafe_function(name))
continue;
ks = search_kallsyms_custom_local(ksyms, name, search_kallsyms_compare);
@@ -728,7 +728,7 @@ int bpf_get_addrs(unsigned long **addrsp, size_t *cntp, bool kernel)
free(name);
if (sscanf(buf, "%p %ms$*[^\n]\n", &addr, &name) != 2)
continue;
- if (skip_entry(name))
+ if (is_unsafe_function(name))
continue;
if (cnt == max_cnt) {
diff --git a/tools/testing/selftests/bpf/trace_helpers.h b/tools/testing/selftests/bpf/trace_helpers.h
index d5bf1433675d..01c8ecc45627 100644
--- a/tools/testing/selftests/bpf/trace_helpers.h
+++ b/tools/testing/selftests/bpf/trace_helpers.h
@@ -63,4 +63,5 @@ int read_build_id(const char *path, char *build_id, size_t size);
int bpf_get_ksyms(struct ksyms **ksymsp, bool kernel);
int bpf_get_addrs(unsigned long **addrsp, size_t *cntp, bool kernel);
+bool is_unsafe_function(const char *name);
#endif
--
2.54.0
^ permalink raw reply related [flat|nested] 34+ messages in thread* [PATCHv6 bpf-next 29/29] selftests/bpf: Add tracing multi attach rollback tests
2026-05-27 11:39 [PATCHv6 bpf-next 00/29] bpf: tracing_multi link Jiri Olsa
` (27 preceding siblings ...)
2026-05-27 11:39 ` [PATCHv6 bpf-next 28/29] selftests/bpf: Add tracing multi attach benchmark test Jiri Olsa
@ 2026-05-27 11:39 ` Jiri Olsa
28 siblings, 0 replies; 34+ messages in thread
From: Jiri Olsa @ 2026-05-27 11:39 UTC (permalink / raw)
To: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko
Cc: bpf, linux-trace-kernel, Martin KaFai Lau, Eduard Zingerman,
Song Liu, Yonghong Song, Menglong Dong, Steven Rostedt
Adding tests for the rollback code when the tracing_multi
link won't get attached, covering 2 reasons:
- wrong btf id passed by user, where all previously allocated
trampolines will be released
- trampoline for requested function is fully attached (has already
maximum programs attached) and the link fails, the rollback code
needs to release all previously link-ed trampolines and release
them
We need the bpf_fentry_test* unattached for the tests to pass,
so the rollback tests are serial.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
---
.../selftests/bpf/prog_tests/tracing_multi.c | 212 ++++++++++++++++++
.../bpf/progs/tracing_multi_rollback.c | 43 ++++
2 files changed, 255 insertions(+)
create mode 100644 tools/testing/selftests/bpf/progs/tracing_multi_rollback.c
diff --git a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
index e437e6cec222..036f18bb3d90 100644
--- a/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
+++ b/tools/testing/selftests/bpf/prog_tests/tracing_multi.c
@@ -11,6 +11,7 @@
#include "tracing_multi_fail.skel.h"
#include "tracing_multi_verifier.skel.h"
#include "tracing_multi_bench.skel.h"
+#include "tracing_multi_rollback.skel.h"
#include "trace_helpers.h"
static __u64 bpf_fentry_test_cookies[] = {
@@ -687,6 +688,217 @@ void serial_test_tracing_multi_bench_attach(void)
btf__free(btf);
}
+static void tracing_multi_rollback_run(struct tracing_multi_rollback *skel)
+{
+ LIBBPF_OPTS(bpf_test_run_opts, topts);
+ int err, prog_fd;
+
+ prog_fd = bpf_program__fd(skel->progs.test_fentry);
+ err = bpf_prog_test_run_opts(prog_fd, &topts);
+ ASSERT_OK(err, "test_run");
+
+ /* make sure the rollback code did not leave any program attached */
+ ASSERT_EQ(skel->bss->test_result_fentry, 0, "test_result_fentry");
+ ASSERT_EQ(skel->bss->test_result_fexit, 0, "test_result_fexit");
+}
+
+static void test_rollback_put(void)
+{
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi_rollback *skel = NULL;
+ size_t cnt = FUNCS_CNT;
+ __u32 *ids = NULL;
+ int err;
+
+ skel = tracing_multi_rollback__open();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_rollback__open"))
+ return;
+
+ bpf_program__set_autoload(skel->progs.test_fentry, true);
+ bpf_program__set_autoload(skel->progs.test_fexit, true);
+
+ err = tracing_multi_rollback__load(skel);
+ if (!ASSERT_OK(err, "tracing_multi_rollback__load"))
+ goto cleanup;
+
+ ids = get_ids(bpf_fentry_test, cnt, NULL);
+ if (!ASSERT_OK_PTR(ids, "get_ids"))
+ goto cleanup;
+
+ /*
+ * Mangle last id to trigger rollback, which needs to do put
+ * on get-ed trampolines.
+ */
+ ids[9] = 0;
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ skel->bss->pid = getpid();
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ if (!ASSERT_ERR_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ NULL, &opts);
+ if (!ASSERT_ERR_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ /* We don't really attach any program, but let's make sure. */
+ tracing_multi_rollback_run(skel);
+
+cleanup:
+ tracing_multi_rollback__destroy(skel);
+ free(ids);
+}
+
+static void fillers_cleanup(struct tracing_multi_rollback **skels, int cnt)
+{
+ int i;
+
+ for (i = 0; i < cnt; i++)
+ tracing_multi_rollback__destroy(skels[i]);
+
+ free(skels);
+}
+
+static struct tracing_multi_rollback *extra_load_and_link(void)
+{
+ struct tracing_multi_rollback *skel;
+ int err;
+
+ skel = tracing_multi_rollback__open();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_rollback__open"))
+ goto cleanup;
+
+ bpf_program__set_autoload(skel->progs.extra, true);
+
+ err = tracing_multi_rollback__load(skel);
+ if (!ASSERT_OK(err, "tracing_multi_rollback__load"))
+ goto cleanup;
+
+ skel->links.extra = bpf_program__attach_trace(skel->progs.extra);
+ if (!ASSERT_OK_PTR(skel->links.extra, "bpf_program__attach_trace"))
+ goto cleanup;
+
+ return skel;
+
+cleanup:
+ tracing_multi_rollback__destroy(skel);
+ return NULL;
+}
+
+static struct tracing_multi_rollback **fillers_load_and_link(int max)
+{
+ struct tracing_multi_rollback **skels, *skel;
+ int i, err;
+
+ skels = calloc(max + 1, sizeof(*skels));
+ if (!ASSERT_OK_PTR(skels, "calloc"))
+ return NULL;
+
+ for (i = 0; i < max; i++) {
+ skel = skels[i] = tracing_multi_rollback__open();
+ if (!ASSERT_OK_PTR(skels[i], "tracing_multi_rollback__open"))
+ goto cleanup;
+
+ bpf_program__set_autoload(skel->progs.filler, true);
+
+ err = tracing_multi_rollback__load(skel);
+ if (!ASSERT_OK(err, "tracing_multi_rollback__load"))
+ goto cleanup;
+
+ skel->links.filler = bpf_program__attach_trace(skel->progs.filler);
+ if (!ASSERT_OK_PTR(skels[i]->links.filler, "bpf_program__attach_trace"))
+ goto cleanup;
+ }
+
+ return skels;
+
+cleanup:
+ fillers_cleanup(skels, i + 1);
+ return NULL;
+}
+
+static void test_rollback_unlink(void)
+{
+ struct tracing_multi_rollback *skel = NULL, *extra;
+ LIBBPF_OPTS(bpf_tracing_multi_opts, opts);
+ struct tracing_multi_rollback **fillers;
+ size_t cnt = FUNCS_CNT;
+ __u32 *ids = NULL;
+ int err, max;
+
+ max = get_bpf_max_tramp_links();
+ if (!ASSERT_GE(max, 1, "bpf_max_tramp_links"))
+ return;
+
+ /* Attach maximum allowed programs to bpf_fentry_test10 */
+ fillers = fillers_load_and_link(max);
+ if (!ASSERT_OK_PTR(fillers, "fillers_load_and_link"))
+ return;
+
+ extra = extra_load_and_link();
+ if (!ASSERT_OK_PTR(extra, "extra_load_and_link"))
+ goto cleanup;
+
+ skel = tracing_multi_rollback__open();
+ if (!ASSERT_OK_PTR(skel, "tracing_multi_rollback__open"))
+ goto cleanup;
+
+ bpf_program__set_autoload(skel->progs.test_fentry, true);
+ bpf_program__set_autoload(skel->progs.test_fexit, true);
+
+ /*
+ * Attach tracing_multi link on bpf_fentry_test1-10, which will
+ * fail on bpf_fentry_test10 function, because it already has
+ * maximum allowed programs attached.
+ *
+ * The rollback needs to unlink already link-ed trampolines and
+ * put all of them.
+ */
+ err = tracing_multi_rollback__load(skel);
+ if (!ASSERT_OK(err, "tracing_multi_rollback__load"))
+ goto cleanup;
+
+ ids = get_ids(bpf_fentry_test, cnt, NULL);
+ if (!ASSERT_OK_PTR(ids, "get_ids"))
+ goto cleanup;
+
+ opts.ids = ids;
+ opts.cnt = cnt;
+
+ skel->bss->pid = getpid();
+
+ skel->links.test_fentry = bpf_program__attach_tracing_multi(skel->progs.test_fentry,
+ NULL, &opts);
+ if (!ASSERT_ERR_PTR(skel->links.test_fentry, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ skel->links.test_fexit = bpf_program__attach_tracing_multi(skel->progs.test_fexit,
+ NULL, &opts);
+ if (!ASSERT_ERR_PTR(skel->links.test_fexit, "bpf_program__attach_tracing_multi"))
+ goto cleanup;
+
+ tracing_multi_rollback_run(skel);
+
+cleanup:
+ fillers_cleanup(fillers, max);
+ tracing_multi_rollback__destroy(extra);
+ tracing_multi_rollback__destroy(skel);
+ free(ids);
+}
+
+void serial_test_tracing_multi_attach_rollback(void)
+{
+ if (test__start_subtest("put"))
+ test_rollback_put();
+ if (test__start_subtest("unlink"))
+ test_rollback_unlink();
+}
+
void test_tracing_multi_test(void)
{
#ifndef __x86_64__
diff --git a/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c b/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c
new file mode 100644
index 000000000000..a49d1d841f3a
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/tracing_multi_rollback.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <vmlinux.h>
+#include <bpf/bpf_helpers.h>
+#include <bpf/bpf_tracing.h>
+
+char _license[] SEC("license") = "GPL";
+
+int pid = 0;
+
+__u64 test_result_fentry = 0;
+__u64 test_result_fexit = 0;
+
+SEC("?fentry.multi")
+int BPF_PROG(test_fentry)
+{
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ test_result_fentry++;
+ return 0;
+}
+
+SEC("?fexit.multi")
+int BPF_PROG(test_fexit)
+{
+ if (bpf_get_current_pid_tgid() >> 32 != pid)
+ return 0;
+
+ test_result_fexit++;
+ return 0;
+}
+
+SEC("?fentry/bpf_fentry_test1")
+int BPF_PROG(extra)
+{
+ return 0;
+}
+
+SEC("?fentry/bpf_fentry_test10")
+int BPF_PROG(filler)
+{
+ return 0;
+}
--
2.54.0
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