* [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi
@ 2025-06-12 11:55 Tao Chen
2025-06-12 11:55 ` [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi Tao Chen
2025-06-12 21:27 ` [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Andrii Nakryiko
0 siblings, 2 replies; 7+ messages in thread
From: Tao Chen @ 2025-06-12 11:55 UTC (permalink / raw)
To: ast, daniel, andrii, martin.lau, eddyz87, song, yonghong.song,
john.fastabend, kpsingh, sdf, haoluo, jolsa, mattbobrowski,
rostedt, mhiramat, mathieu.desnoyers
Cc: bpf, linux-kernel, linux-trace-kernel, Tao Chen
Show uprobe_multi link info with fdinfo, the info as follows:
link_type: uprobe_multi
link_id: 9
prog_tag: e729f789e34a8eca
prog_id: 39
type: uprobe_multi
func_cnt: 3
pid: 0
path: /home/dylane/bpf/tools/testing/selftests/bpf/test_progs
offset: 0xa69ed7
ref_ctr_offset: 0x0
cookie: 3
offset: 0xa69ee2
ref_ctr_offset: 0x0
cookie: 1
offset: 0xa69eed
ref_ctr_offset: 0x0
cookie: 2
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
kernel/trace/bpf_trace.c | 48 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 48 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 24b94870b50..c4ad82b8fd8 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -3157,10 +3157,58 @@ static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link,
return err;
}
+#ifdef CONFIG_PROC_FS
+static void bpf_uprobe_multi_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_uprobe_multi_link *umulti_link;
+ char *p, *buf;
+
+ umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
+
+ buf = kmalloc(PATH_MAX, GFP_KERNEL);
+ if (!buf)
+ return;
+
+ p = d_path(&umulti_link->path, buf, PATH_MAX);
+ if (IS_ERR(p)) {
+ kfree(buf);
+ return;
+ }
+
+ seq_printf(seq,
+ "type:\t%s\n"
+ "func_cnt:\t%u\n"
+ "pid:\t%u\n"
+ "path:\t%s\n",
+ umulti_link->flags == BPF_F_UPROBE_MULTI_RETURN ?
+ "uretprobe_multi" : "uprobe_multi",
+ umulti_link->cnt,
+ umulti_link->task ? task_pid_nr_ns(umulti_link->task,
+ task_active_pid_ns(current)) : 0,
+ p);
+
+ for (int i = 0; i < umulti_link->cnt; i++) {
+ seq_printf(seq,
+ "offset:\t%#llx\n"
+ "ref_ctr_offset:\t%#lx\n"
+ "cookie:\t%llu\n",
+ umulti_link->uprobes[i].offset,
+ umulti_link->uprobes[i].ref_ctr_offset,
+ umulti_link->uprobes[i].cookie);
+ }
+
+ kfree(buf);
+}
+#endif
+
static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
.release = bpf_uprobe_multi_link_release,
.dealloc_deferred = bpf_uprobe_multi_link_dealloc,
.fill_link_info = bpf_uprobe_multi_link_fill_link_info,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = bpf_uprobe_multi_show_fdinfo,
+#endif
};
static int uprobe_prog_run(struct bpf_uprobe *uprobe,
--
2.48.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi
2025-06-12 11:55 [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Tao Chen
@ 2025-06-12 11:55 ` Tao Chen
2025-06-12 16:01 ` Alexei Starovoitov
2025-06-12 21:27 ` [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Andrii Nakryiko
1 sibling, 1 reply; 7+ messages in thread
From: Tao Chen @ 2025-06-12 11:55 UTC (permalink / raw)
To: ast, daniel, andrii, martin.lau, eddyz87, song, yonghong.song,
john.fastabend, kpsingh, sdf, haoluo, jolsa, mattbobrowski,
rostedt, mhiramat, mathieu.desnoyers
Cc: bpf, linux-kernel, linux-trace-kernel, Tao Chen
Show kprobe_multi link info with fdinfo, the info as follows:
link_type: kprobe_multi
link_id: 4
prog_tag: 279dd9c09dfbc757
prog_id: 30
type: kprobe_multi
func_cnt: 8
missed: 0
addr: 0xffffffff81ecb1e0
cookie: 8
addr: 0xffffffff81eccb70
cookie: 2
addr: 0xffffffff81eccba0
cookie: 7
addr: 0xffffffff81eccbd0
cookie: 6
addr: 0xffffffff81eccc00
cookie: 5
addr: 0xffffffff81eccc30
cookie: 4
addr: 0xffffffff81eccc60
cookie: 3
addr: 0xffffffff81eccc90
cookie: 1
Signed-off-by: Tao Chen <chen.dylane@linux.dev>
---
kernel/trace/bpf_trace.c | 31 +++++++++++++++++++++++++++++++
1 file changed, 31 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index c4ad82b8fd8..6c3ffa3c1ca 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -2623,10 +2623,41 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link,
return err;
}
+#ifdef CONFIG_PROC_FS
+static void bpf_kprobe_multi_show_fdinfo(const struct bpf_link *link,
+ struct seq_file *seq)
+{
+ struct bpf_kprobe_multi_link *kmulti_link;
+
+ kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link);
+
+ seq_printf(seq,
+ "type:\t%s\n"
+ "func_cnt:\t%u\n"
+ "missed:\t%lu\n",
+ kmulti_link->flags == BPF_F_KPROBE_MULTI_RETURN ? "kretprobe_multi" :
+ "kprobe_multi",
+ kmulti_link->cnt,
+ kmulti_link->fp.nmissed);
+
+ for (int i = 0; i < kmulti_link->cnt; i++) {
+ seq_printf(seq,
+ "addr:\t%#lx\n"
+ "cookie:\t%llu\n",
+ kmulti_link->addrs[i],
+ kmulti_link->cookies[i]
+ );
+ }
+}
+#endif
+
static const struct bpf_link_ops bpf_kprobe_multi_link_lops = {
.release = bpf_kprobe_multi_link_release,
.dealloc_deferred = bpf_kprobe_multi_link_dealloc,
.fill_link_info = bpf_kprobe_multi_link_fill_link_info,
+#ifdef CONFIG_PROC_FS
+ .show_fdinfo = bpf_kprobe_multi_show_fdinfo,
+#endif
};
static void bpf_kprobe_multi_cookie_swap(void *a, void *b, int size, const void *priv)
--
2.48.1
^ permalink raw reply related [flat|nested] 7+ messages in thread
* Re: [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi
2025-06-12 11:55 ` [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi Tao Chen
@ 2025-06-12 16:01 ` Alexei Starovoitov
2025-06-13 2:52 ` Tao Chen
0 siblings, 1 reply; 7+ messages in thread
From: Alexei Starovoitov @ 2025-06-12 16:01 UTC (permalink / raw)
To: Tao Chen
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard, Song Liu, Yonghong Song, John Fastabend,
KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, Matt Bobrowski,
Steven Rostedt, Masami Hiramatsu, Mathieu Desnoyers, bpf, LKML,
linux-trace-kernel
On Thu, Jun 12, 2025 at 4:56 AM Tao Chen <chen.dylane@linux.dev> wrote:
>
> Show kprobe_multi link info with fdinfo, the info as follows:
>
> link_type: kprobe_multi
> link_id: 4
> prog_tag: 279dd9c09dfbc757
> prog_id: 30
> type: kprobe_multi
> func_cnt: 8
> missed: 0
> addr: 0xffffffff81ecb1e0
fdinfo shouldn't print kernel addresses.
It defeats kaslr
pw-bot: cr
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi
2025-06-12 11:55 [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Tao Chen
2025-06-12 11:55 ` [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi Tao Chen
@ 2025-06-12 21:27 ` Andrii Nakryiko
2025-06-13 2:28 ` Tao Chen
1 sibling, 1 reply; 7+ messages in thread
From: Andrii Nakryiko @ 2025-06-12 21:27 UTC (permalink / raw)
To: Tao Chen
Cc: ast, daniel, andrii, martin.lau, eddyz87, song, yonghong.song,
john.fastabend, kpsingh, sdf, haoluo, jolsa, mattbobrowski,
rostedt, mhiramat, mathieu.desnoyers, bpf, linux-kernel,
linux-trace-kernel
On Thu, Jun 12, 2025 at 4:56 AM Tao Chen <chen.dylane@linux.dev> wrote:
>
> Show uprobe_multi link info with fdinfo, the info as follows:
>
> link_type: uprobe_multi
> link_id: 9
> prog_tag: e729f789e34a8eca
> prog_id: 39
> type: uprobe_multi
> func_cnt: 3
> pid: 0
> path: /home/dylane/bpf/tools/testing/selftests/bpf/test_progs
> offset: 0xa69ed7
> ref_ctr_offset: 0x0
> cookie: 3
> offset: 0xa69ee2
> ref_ctr_offset: 0x0
> cookie: 1
> offset: 0xa69eed
> ref_ctr_offset: 0x0
> cookie: 2
>
> Signed-off-by: Tao Chen <chen.dylane@linux.dev>
> ---
> kernel/trace/bpf_trace.c | 48 ++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 48 insertions(+)
>
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index 24b94870b50..c4ad82b8fd8 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -3157,10 +3157,58 @@ static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link,
> return err;
> }
>
> +#ifdef CONFIG_PROC_FS
> +static void bpf_uprobe_multi_show_fdinfo(const struct bpf_link *link,
> + struct seq_file *seq)
> +{
> + struct bpf_uprobe_multi_link *umulti_link;
> + char *p, *buf;
> +
> + umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
> +
> + buf = kmalloc(PATH_MAX, GFP_KERNEL);
> + if (!buf)
> + return;
> +
> + p = d_path(&umulti_link->path, buf, PATH_MAX);
> + if (IS_ERR(p)) {
> + kfree(buf);
> + return;
> + }
> +
> + seq_printf(seq,
> + "type:\t%s\n"
> + "func_cnt:\t%u\n"
it's not really *func* (e.g., for USDTs it's basically guaranteed to
be somewhere inside the function, potentially in many places within
the same function), I'd use generic "uprobe_{cnt,count}"
> + "pid:\t%u\n"
> + "path:\t%s\n",
> + umulti_link->flags == BPF_F_UPROBE_MULTI_RETURN ?
> + "uretprobe_multi" : "uprobe_multi",
> + umulti_link->cnt,
> + umulti_link->task ? task_pid_nr_ns(umulti_link->task,
> + task_active_pid_ns(current)) : 0,
> + p);
> +
> + for (int i = 0; i < umulti_link->cnt; i++) {
> + seq_printf(seq,
> + "offset:\t%#llx\n"
> + "ref_ctr_offset:\t%#lx\n"
> + "cookie:\t%llu\n",
> + umulti_link->uprobes[i].offset,
> + umulti_link->uprobes[i].ref_ctr_offset,
> + umulti_link->uprobes[i].cookie);
> + }
> +
> + kfree(buf);
> +}
> +#endif
> +
> static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
> .release = bpf_uprobe_multi_link_release,
> .dealloc_deferred = bpf_uprobe_multi_link_dealloc,
> .fill_link_info = bpf_uprobe_multi_link_fill_link_info,
> +#ifdef CONFIG_PROC_FS
> + .show_fdinfo = bpf_uprobe_multi_show_fdinfo,
> +#endif
> };
>
> static int uprobe_prog_run(struct bpf_uprobe *uprobe,
> --
> 2.48.1
>
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi
2025-06-12 21:27 ` [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Andrii Nakryiko
@ 2025-06-13 2:28 ` Tao Chen
0 siblings, 0 replies; 7+ messages in thread
From: Tao Chen @ 2025-06-13 2:28 UTC (permalink / raw)
To: Andrii Nakryiko
Cc: ast, daniel, andrii, martin.lau, eddyz87, song, yonghong.song,
john.fastabend, kpsingh, sdf, haoluo, jolsa, mattbobrowski,
rostedt, mhiramat, mathieu.desnoyers, bpf, linux-kernel,
linux-trace-kernel
在 2025/6/13 05:27, Andrii Nakryiko 写道:
> On Thu, Jun 12, 2025 at 4:56 AM Tao Chen <chen.dylane@linux.dev> wrote:
>>
>> Show uprobe_multi link info with fdinfo, the info as follows:
>>
>> link_type: uprobe_multi
>> link_id: 9
>> prog_tag: e729f789e34a8eca
>> prog_id: 39
>> type: uprobe_multi
>> func_cnt: 3
>> pid: 0
>> path: /home/dylane/bpf/tools/testing/selftests/bpf/test_progs
>> offset: 0xa69ed7
>> ref_ctr_offset: 0x0
>> cookie: 3
>> offset: 0xa69ee2
>> ref_ctr_offset: 0x0
>> cookie: 1
>> offset: 0xa69eed
>> ref_ctr_offset: 0x0
>> cookie: 2
>>
>> Signed-off-by: Tao Chen <chen.dylane@linux.dev>
>> ---
>> kernel/trace/bpf_trace.c | 48 ++++++++++++++++++++++++++++++++++++++++
>> 1 file changed, 48 insertions(+)
>>
>> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
>> index 24b94870b50..c4ad82b8fd8 100644
>> --- a/kernel/trace/bpf_trace.c
>> +++ b/kernel/trace/bpf_trace.c
>> @@ -3157,10 +3157,58 @@ static int bpf_uprobe_multi_link_fill_link_info(const struct bpf_link *link,
>> return err;
>> }
>>
>> +#ifdef CONFIG_PROC_FS
>> +static void bpf_uprobe_multi_show_fdinfo(const struct bpf_link *link,
>> + struct seq_file *seq)
>> +{
>> + struct bpf_uprobe_multi_link *umulti_link;
>> + char *p, *buf;
>> +
>> + umulti_link = container_of(link, struct bpf_uprobe_multi_link, link);
>> +
>> + buf = kmalloc(PATH_MAX, GFP_KERNEL);
>> + if (!buf)
>> + return;
>> +
>> + p = d_path(&umulti_link->path, buf, PATH_MAX);
>> + if (IS_ERR(p)) {
>> + kfree(buf);
>> + return;
>> + }
>> +
>> + seq_printf(seq,
>> + "type:\t%s\n"
>> + "func_cnt:\t%u\n"
>
> it's not really *func* (e.g., for USDTs it's basically guaranteed to
> be somewhere inside the function, potentially in many places within
> the same function), I'd use generic "uprobe_{cnt,count}"
>
>
will change it in v2, thanks for the advice.
>> + "pid:\t%u\n"
>> + "path:\t%s\n",
>> + umulti_link->flags == BPF_F_UPROBE_MULTI_RETURN ?
>> + "uretprobe_multi" : "uprobe_multi",
>> + umulti_link->cnt,
>> + umulti_link->task ? task_pid_nr_ns(umulti_link->task,
>> + task_active_pid_ns(current)) : 0,
>> + p);
>> +
>> + for (int i = 0; i < umulti_link->cnt; i++) {
>> + seq_printf(seq,
>> + "offset:\t%#llx\n"
>> + "ref_ctr_offset:\t%#lx\n"
>> + "cookie:\t%llu\n",
>> + umulti_link->uprobes[i].offset,
>> + umulti_link->uprobes[i].ref_ctr_offset,
>> + umulti_link->uprobes[i].cookie);
>> + }
>> +
>> + kfree(buf);
>> +}
>> +#endif
>> +
>> static const struct bpf_link_ops bpf_uprobe_multi_link_lops = {
>> .release = bpf_uprobe_multi_link_release,
>> .dealloc_deferred = bpf_uprobe_multi_link_dealloc,
>> .fill_link_info = bpf_uprobe_multi_link_fill_link_info,
>> +#ifdef CONFIG_PROC_FS
>> + .show_fdinfo = bpf_uprobe_multi_show_fdinfo,
>> +#endif
>> };
>>
>> static int uprobe_prog_run(struct bpf_uprobe *uprobe,
>> --
>> 2.48.1
>>
--
Best Regards
Tao Chen
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi
2025-06-12 16:01 ` Alexei Starovoitov
@ 2025-06-13 2:52 ` Tao Chen
2025-06-13 17:31 ` Alexei Starovoitov
0 siblings, 1 reply; 7+ messages in thread
From: Tao Chen @ 2025-06-13 2:52 UTC (permalink / raw)
To: Alexei Starovoitov
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard, Song Liu, Yonghong Song, John Fastabend,
KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, Matt Bobrowski,
Steven Rostedt, Masami Hiramatsu, Mathieu Desnoyers, bpf, LKML,
linux-trace-kernel
在 2025/6/13 00:01, Alexei Starovoitov 写道:
> On Thu, Jun 12, 2025 at 4:56 AM Tao Chen <chen.dylane@linux.dev> wrote:
>>
>> Show kprobe_multi link info with fdinfo, the info as follows:
>>
>> link_type: kprobe_multi
>> link_id: 4
>> prog_tag: 279dd9c09dfbc757
>> prog_id: 30
>> type: kprobe_multi
>> func_cnt: 8
>> missed: 0
>> addr: 0xffffffff81ecb1e0
>
> fdinfo shouldn't print kernel addresses.
> It defeats kaslr
>
How about print the function name corresponding of the address, or
don't show the addr info.
> pw-bot: cr
--
Best Regards
Tao Chen
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi
2025-06-13 2:52 ` Tao Chen
@ 2025-06-13 17:31 ` Alexei Starovoitov
0 siblings, 0 replies; 7+ messages in thread
From: Alexei Starovoitov @ 2025-06-13 17:31 UTC (permalink / raw)
To: Tao Chen
Cc: Alexei Starovoitov, Daniel Borkmann, Andrii Nakryiko,
Martin KaFai Lau, Eduard, Song Liu, Yonghong Song, John Fastabend,
KP Singh, Stanislav Fomichev, Hao Luo, Jiri Olsa, Matt Bobrowski,
Steven Rostedt, Masami Hiramatsu, Mathieu Desnoyers, bpf, LKML,
linux-trace-kernel
On Thu, Jun 12, 2025 at 7:52 PM Tao Chen <chen.dylane@linux.dev> wrote:
>
> 在 2025/6/13 00:01, Alexei Starovoitov 写道:
> > On Thu, Jun 12, 2025 at 4:56 AM Tao Chen <chen.dylane@linux.dev> wrote:
> >>
> >> Show kprobe_multi link info with fdinfo, the info as follows:
> >>
> >> link_type: kprobe_multi
> >> link_id: 4
> >> prog_tag: 279dd9c09dfbc757
> >> prog_id: 30
> >> type: kprobe_multi
> >> func_cnt: 8
> >> missed: 0
> >> addr: 0xffffffff81ecb1e0
> >
> > fdinfo shouldn't print kernel addresses.
> > It defeats kaslr
> >
>
> How about print the function name corresponding of the address, or
> don't show the addr info.
Yeah. That would be much better. human readable unlike hex.
^ permalink raw reply [flat|nested] 7+ messages in thread
end of thread, other threads:[~2025-06-13 17:32 UTC | newest]
Thread overview: 7+ messages (download: mbox.gz follow: Atom feed
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2025-06-12 11:55 [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Tao Chen
2025-06-12 11:55 ` [PATCH bpf-next 2/2] bpf: Add show_fdinfo for kprobe_multi Tao Chen
2025-06-12 16:01 ` Alexei Starovoitov
2025-06-13 2:52 ` Tao Chen
2025-06-13 17:31 ` Alexei Starovoitov
2025-06-12 21:27 ` [PATCH bpf-next 1/2] bpf: Add show_fdinfo for uprobe_multi Andrii Nakryiko
2025-06-13 2:28 ` Tao Chen
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