* [PATCH v12 11/11] tracing/probes: Add a new testcase for BTF typecasts
From: Masami Hiramatsu (Google) @ 2026-06-28 23:53 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178269068329.1161310.17763177188897860801.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
With the introduction of container_of-style BTF typecasting and
per-CPU variable access support in trace probes, we need a way to
verify their functionality and prevent regressions.
Add a new ftrace kselftest and update the trace event sample module
to test and validate these features.
Specifically, update the trace-events-sample module to set up a
periodic timer whose callback accesses a per-CPU counter. Introduce
a new sample trace event, foo_timer_fn, to trace this callback
and log the current counter value.
Then, add a new test case, btf_probe_event.tc, which defines a
dynamic probe on the timer callback. The probe uses BTF typecasting
to recover the parent structure from the timer argument and
this_cpu_read() to fetch the per-CPU counter. The test verifies
the integrity of the implementation by ensuring the values
recorded by the dynamic probe match those from the static tracepoint.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v12:
- Fix current support check in eprobe testcase.
- Fix to return UNRESOLVED error if sample module is not found.
- Always check this_cpu_* in btf_typecast_accepted.tc.
Changes in v11:
- nit: fix the error code in comment.
Changes in v10:
- Add a check for $current and this_cpu_* for eprobe
Changes in v9:
- Add a testcase for checking new syntax.
Changes in v8:
- Add more test cases.
Changes in v6:
- Update testcase according to changes.
Changes in v5:
- Add more syntax test cases.
Changes in v4:
- Fix uprobe $current test.
Changes in v3:
- Add syntax test case.
- Update testcase to use this_cpu_read()
Changes in v2:
- Use timer_shutdown_sync() instead of timer_delete_sync() for teardown.
---
samples/trace_events/trace-events-sample.c | 40 +++++++-
samples/trace_events/trace-events-sample.h | 34 ++++++-
.../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++++++++++
.../test.d/dynevent/btf_typecast_accepted.tc | 103 ++++++++++++++++++++
.../test.d/dynevent/eprobes_syntax_errors.tc | 9 ++
.../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 12 ++
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 12 ++
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5 +
8 files changed, 261 insertions(+), 5 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index 0b7a6efdb247..ca5d98c360cb 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -94,6 +94,20 @@ static int simple_thread_fn(void *arg)
static DEFINE_MUTEX(thread_mutex);
static int simple_thread_cnt;
+static struct foo_timer_data *foo_timer_data;
+
+static void sample_timer_cb(struct timer_list *t)
+{
+ struct foo_timer_data *data = container_of(t, struct foo_timer_data, timer);
+
+ get_cpu();
+ trace_foo_timer_fn(data);
+ (*this_cpu_ptr(data->counter))++;
+ put_cpu();
+
+ mod_timer(t, jiffies + HZ);
+}
+
int foo_bar_reg(void)
{
mutex_lock(&thread_mutex);
@@ -132,9 +146,27 @@ void foo_bar_unreg(void)
static int __init trace_event_init(void)
{
+ foo_timer_data = kzalloc_obj(*foo_timer_data, GFP_KERNEL);
+ if (!foo_timer_data)
+ return -ENOMEM;
+
+ foo_timer_data->name = "sample_timer_counter";
+ foo_timer_data->counter = alloc_percpu(int);
+ if (!foo_timer_data->counter) {
+ kfree(foo_timer_data);
+ return -ENOMEM;
+ }
+
+ timer_setup(&foo_timer_data->timer, sample_timer_cb, 0);
+ mod_timer(&foo_timer_data->timer, jiffies + HZ);
+
simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
- if (IS_ERR(simple_tsk))
- return -1;
+ if (IS_ERR(simple_tsk)) {
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
+ return PTR_ERR(simple_tsk);
+ }
return 0;
}
@@ -147,6 +179,10 @@ static void __exit trace_event_exit(void)
kthread_stop(simple_tsk_fn);
simple_tsk_fn = NULL;
mutex_unlock(&thread_mutex);
+
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
}
module_init(trace_event_init);
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 1a05fc153353..816848a456a2 100644
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -247,12 +247,14 @@
*/
/*
- * It is OK to have helper functions in the file, but they need to be protected
- * from being defined more than once. Remember, this file gets included more
- * than once.
+ * It is OK to have helper functions and data structures in the file, but they
+ * need to be protected from being defined more than once. Remember, this file
+ * gets included more than once.
*/
#ifndef __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
#define __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
+#include <linux/timer.h>
+
static inline int __length_of(const int *list)
{
int i;
@@ -270,6 +272,13 @@ enum {
TRACE_SAMPLE_BAR = 4,
TRACE_SAMPLE_ZOO = 8,
};
+
+struct foo_timer_data {
+ const char *name;
+ struct timer_list timer;
+ int __percpu *counter;
+};
+
#endif
/*
@@ -595,6 +604,25 @@ TRACE_EVENT(foo_rel_loc,
__get_rel_bitmask(bitmask),
__get_rel_cpumask(cpumask))
);
+
+TRACE_EVENT(foo_timer_fn,
+
+ TP_PROTO(struct foo_timer_data *data),
+
+ TP_ARGS(data),
+
+ TP_STRUCT__entry(
+ __string( name, data->name )
+ __field( int, count )
+ ),
+
+ TP_fast_assign(
+ __assign_str(name);
+ __entry->count = *this_cpu_ptr(data->counter);
+ ),
+
+ TP_printk("name=%s count=%d", __get_str(name), __entry->count)
+);
#endif
/***** NOTICE! The #if protection ends here. *****/
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
new file mode 100644
index 000000000000..bf71368c31a4
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
@@ -0,0 +1,51 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: BTF event with typecast and percpu access
+# requires: dynamic_events "this_cpu_read(<fetcharg>)":README "[(structname[,field])]<argname>[->field[->field|.field...]]":README
+
+# Check if the sample module is loaded
+if ! lsmod | grep -q trace_events_sample; then
+ modprobe trace-events-sample || exit_unresolved
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# The sample_timer_cb(struct timer_list *t) is called.
+# We want to check (STRUCT,FIELD)VAR typecast and this_cpu_read() access.
+# (foo_timer_data,timer)t converts t to struct foo_timer_data * using container_of.
+# data->counter is a per-cpu pointer to int.
+# this_cpu_read(data->counter) should give the value of the counter.
+
+echo 'f:mysample/myevent sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+
+echo 1 > events/mysample/myevent/enable
+echo 1 > events/sample-trace/foo_timer_fn/enable
+
+sleep 2
+
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+
+# Compare the values.
+MATCH=0
+while read line; do
+ if echo $line | grep -q "foo_timer_fn:"; then
+ NAME=`echo $line | sed 's/.*name=\([^ ]*\) .*/\1/'`
+ COUNT=`echo $line | sed 's/.*count=\([^ ]*\).*/\1/'`
+ if grep -q "myevent:.*name=\"${NAME}\" count=$COUNT" trace; then
+ MATCH=$((MATCH+1))
+ fi
+ fi
+done < trace
+
+if [ $MATCH -eq 0 ]; then
+ echo "No matching events found"
+ exit_fail
+fi
+
+# Clean up
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+echo > dynamic_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc b/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
new file mode 100644
index 000000000000..dd5552727054
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
@@ -0,0 +1,103 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: BTF typecast and percpu access syntax validation
+# requires: dynamic_events "this_cpu_read(<fetcharg>)":README "[(structname[,field])]<argname>[->field[->field|.field...]]":README
+
+KPROBES=
+FPROBES=
+
+if grep -qF "p[:[<group>/][<event>]] <place> [<args>]" README ; then
+ KPROBES=yes
+fi
+if grep -qF "f[:[<group>/][<event>]] <func-name>[%return] [<args>]" README ; then
+ FPROBES=yes
+fi
+
+if [ -z "$KPROBES" -a -z "$FPROBES" ] ; then
+ exit_unsupported
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# Load trace-events-sample module if available to have per-CPU counter structure defined
+if ! lsmod | grep -q trace_events_sample; then
+ modprobe trace-events-sample || exit_unresolved
+fi
+
+if [ "$FPROBES" ] ; then
+ # 1. Test basic typecast on fprobe
+ echo 'f:fpevent1 vfs_read name=(file)file->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 2. Test parenthesized typecast target on fprobe
+ echo 'f:fpevent2 vfs_read name=(file)(file)->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 3. Test nested typecasts on fprobe
+ echo 'f:fpevent3 vfs_read name=(dentry)((file)file->f_path.dentry)->d_name.name:string' >> dynamic_events
+ # 4. Test container_of-style typecast with field option on fprobe
+ echo 'f:fpevent4 vfs_read name=(file,f_path)file->f_mode' >> dynamic_events
+ # 5. Test typecast on return value on fprobe
+ echo 'f:fpevent5 vfs_read%return name=(file)$retval->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 6. Test $current variable support on fprobe
+ echo 'f:fpevent6 vfs_read pid=$current->pid' >> dynamic_events
+ echo 'f:fpevent7 vfs_read pid=(task_struct)$current->pid' >> dynamic_events
+ echo 'f:fpevent8 vfs_read pid=(task_struct,group_leader)$current->pid' >> dynamic_events
+
+ # Test this_cpu_read and this_cpu_ptr on fprobe
+ echo 'f:fpevent9 sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+ echo 'f:fpevent10 sample_timer_cb ptr=this_cpu_ptr((foo_timer_data,timer)t->counter)' >> dynamic_events
+fi
+
+if [ "$KPROBES" ] ; then
+ # 7. Test basic typecast on kprobe
+ echo 'p:kpevent1 vfs_read name=(file)file->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 8. Test parenthesized typecast target on kprobe
+ echo 'p:kpevent2 vfs_read name=(file)(file)->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 9. Test nested typecasts on kprobe
+ echo 'p:kpevent3 vfs_read name=(dentry)((file)file->f_path.dentry)->d_name.name:string' >> dynamic_events
+ # 10. Test container_of-style typecast with field option on kprobe
+ echo 'p:kpevent4 vfs_read name=(file,f_path)file->f_mode' >> dynamic_events
+ # 11. Test typecast on return value on kretprobe
+ echo 'r:kpevent5 vfs_read name=(file)$retval->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 12. Test $current variable support on kprobe
+ echo 'p:kpevent6 vfs_read pid=$current->pid' >> dynamic_events
+ echo 'p:kpevent7 vfs_read pid=(task_struct)$current->pid' >> dynamic_events
+ echo 'p:kpevent8 vfs_read pid=(task_struct,group_leader)$current->pid' >> dynamic_events
+
+ # Test this_cpu_read and this_cpu_ptr on kprobe
+ echo 'p:kpevent9 sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+ echo 'p:kpevent10 sample_timer_cb ptr=this_cpu_ptr((foo_timer_data,timer)t->counter)' >> dynamic_events
+fi
+
+# Verify the events exist in dynamic_events
+if [ "$FPROBES" ] ; then
+ grep -q "fpevent1 " dynamic_events
+ grep -q "fpevent2 " dynamic_events
+ grep -q "fpevent3 " dynamic_events
+ grep -q "fpevent4 " dynamic_events
+ grep -q "fpevent5 " dynamic_events
+ grep -q "fpevent6 " dynamic_events
+ grep -q "fpevent7 " dynamic_events
+ grep -q "fpevent8 " dynamic_events
+ if lsmod | grep -q trace_events_sample; then
+ grep -q "fpevent9 " dynamic_events
+ grep -q "fpevent10 " dynamic_events
+ fi
+fi
+
+if [ "$KPROBES" ] ; then
+ grep -q "kpevent1 " dynamic_events
+ grep -q "kpevent2 " dynamic_events
+ grep -q "kpevent3 " dynamic_events
+ grep -q "kpevent4 " dynamic_events
+ grep -q "kpevent5 " dynamic_events
+ grep -q "kpevent6 " dynamic_events
+ grep -q "kpevent7 " dynamic_events
+ grep -q "kpevent8 " dynamic_events
+ if lsmod | grep -q trace_events_sample; then
+ grep -q "kpevent9 " dynamic_events
+ grep -q "kpevent10 " dynamic_events
+ fi
+fi
+
+# Clean up
+echo > dynamic_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
index 0e65e787e426..c2e3f9d19f13 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
@@ -21,8 +21,17 @@ check_error 'e:foo/^bar.1 syscalls/sys_enter_openat' # BAD_EVENT_NAME
check_error 'e:foo/bar syscalls/sys_enter_openat arg=^$foo' # BAD_ATTACH_ARG
+check_error 'e:foo/bar syscalls/sys_enter_openat arg=^COMM' # NO_EVENT_FIELD
+if grep -q "\$current.*" README; then
+ check_error 'e:foo/bar syscalls/sys_enter_openat arg=^current' # NO_EVENT_FIELD
+fi
+
if grep -q '<attached-group>\.<attached-event>.*\[if <filter>\]' README; then
check_error 'e:foo/bar syscalls/sys_enter_openat if ^' # NO_EP_FILTER
fi
+if grep -q 'this_cpu_read(<fetcharg>)' README; then
+ check_error 'e:foo/bar syscalls/sys_enter_openat arg=^this_cpu_read(file)' # NOSUP_PERCPU
+fi
+
exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
index fee479295e2f..e9d7e6919c7f 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
@@ -112,6 +112,18 @@ check_error 'f vfs_read%return $retval->^foo' # NO_PTR_STRCT
check_error 'f vfs_read file->^foo' # NO_BTF_FIELD
check_error 'f vfs_read file^-.foo' # BAD_HYPHEN
check_error 'f vfs_read ^file:string' # BAD_TYPE4STR
+if grep -qF "[(structname" README ; then
+check_error 'f vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'f vfs_read arg1=(a)((b)((c)(^(d)file->d)->c)->b)->a' # TOO_MANY_NESTED
+check_error 'f vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'f vfs_read arg1=(task_struct,^foo_bar)file->pid' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(^task_struct1234)file->pid' # NO_PTR_STRCT
+check_error 'f vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'f vfs_read arg1=(task_struct,^->pid)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct,^.pid)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct,^.)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct)^@symbol+10->comm' # TYPECAST_SYM_OFFSET
+fi
fi
else
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
index 8f1c58f0c239..21ce8414459f 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
@@ -115,6 +115,18 @@ check_error 'p vfs_read+20 ^$arg*' # NOFENTRY_ARGS
check_error 'p vfs_read ^hoge' # NO_BTFARG
check_error 'p kfree ^$arg10' # NO_BTFARG (exceed the number of parameters)
check_error 'r kfree ^$retval' # NO_RETVAL
+if grep -qF "[(structname" README ; then
+check_error 'p vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'p vfs_read arg1=(a)((b)((c)(^(d)file->d)->c)->b)->a' # TOO_MANY_NESTED
+check_error 'p vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'p vfs_read arg1=(task_struct,^foo_bar)file->pid' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(^task_struct1234)file->pid' # NO_PTR_STRCT
+check_error 'p vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'p vfs_read arg1=(task_struct,^->pid)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct,^.pid)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct,^.)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct)^@symbol+10->comm' # TYPECAST_SYM_OFFSET
+fi
else
check_error 'p vfs_read ^$arg*' # NOSUP_BTFARG
fi
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
index c817158b99db..e12dc967ec76 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
@@ -28,4 +28,9 @@ if grep -q ".*symstr.*" README; then
check_error 'p /bin/sh:10 $stack0:^symstr' # BAD_TYPE
fi
+# $current is not supported by uprobe
+if grep -q "\$current.*" README; then
+check_error 'p /bin/sh:10 ^$current:u8' # BAD_VAR
+fi
+
exit 0
^ permalink raw reply related
* Re: [PATCH v4 0/3] mm: clean up folio LRU and swap declarations
From: Jianyue Wu @ 2026-06-29 0:20 UTC (permalink / raw)
To: Andrew Morton
Cc: Chris Li, Kairui Song, Kemeng Shi, Nhat Pham, Baoquan He,
Barry Song, Youngjun Park, Qi Zheng, Shakeel Butt, Axel Rasmussen,
Yuanchu Xie, Wei Xu, Johannes Weiner, David Hildenbrand,
Michal Hocko, Lorenzo Stoakes, Liam R. Howlett, Vlastimil Babka,
Mike Rapoport, Suren Baghdasaryan, Michal Hocko, Hugh Dickins,
Baolin Wang, Jonathan Corbet, Shuah Khan, linux-mm, linux-kernel,
linux-doc
In-Reply-To: <20260628140322.c3ce1a7428d6c6d021069e7d@linux-foundation.org>
On Mon, Jun 29, 2026 at 5:03 AM Andrew Morton <akpm@linux-foundation.org> wrote:
>
> On Wed, 03 Jun 2026 21:05:31 +0800 Jianyue Wu <wujianyue000@gmail.com> wrote:
>
> > The previous version moved the folio LRU helpers out of mm/swap.c in
> > one step. Based on review feedback from Johannes, Baoquan and Barry,
> > split the cleanup into smaller steps:
> >
> > - move the page-cluster sysctl next to swap readahead in mm/swap_state.c
> > - rename mm/swap.c to mm/folio_lru.c after the swap-specific bits move out
> > - move MM-internal reclaim declarations out of include/linux/swap.h
> >
> > After this series, swap cache and swap-in readahead stay in mm/swap_state.c,
> > folio LRU helpers live in mm/folio_lru.c, and MM-internal reclaim/workingset
> > declarations move from include/linux/swap.h to mm/internal.h (public LRU
> > helpers used outside mm/ remain in swap.h).
> >
> > The first patch handles the swap-specific page-cluster state before the
> > file rename, so the rename commit only carries folio LRU code. The last
> > patch keeps the LRU helpers used outside mm/ in include/linux/swap.h and
> > moves the internal reclaim/workingset declarations to mm/internal.h.
> >
> > This series is based on Christoph Hellwig's swap_ops series, which
> > moves swap I/O dispatch behind swap_ops and leaves mm/swap.c with less
> > swap-specific state. That makes the folio LRU cleanup more natural to
> > split out on top.
>
> Patchset looks good and is well-reviewed (thanks, all).
>
> But it's a little old and Sashiko was unable to apply it and I'm seeing
> at least one (probably trivial) reject.
>
> So please can you refresh, retest, gather the ack/review tags and
> resend?
>
> Thanks.
Hello Andrew,
Thanks indeed, I'll do it and resend:)
Best regards,
Jianyue
^ permalink raw reply
* Re: [PATCH] crypto: af_alg - Add af_alg_restrict sysctl, defaulting to 1
From: Simon Richter @ 2026-06-29 3:11 UTC (permalink / raw)
To: Eric Biggers, Demi Marie Obenour
Cc: Andy Lutomirski, linux-crypto, Herbert Xu, linux-kernel,
linux-doc, linux-bluetooth, iwd, linux-hardening, Milan Broz
In-Reply-To: <20260628185404.GA2292@quark>
Hi,
On 6/29/26 3:54 AM, Eric Biggers wrote:
> We could do that if it's what people want. Just keep in mind that it
> would be much more complex than the single tristate sysctl. And in
> practice the number of people who are knowledgeable enough to create
> these lists is quite small; we've seen similar things with other "Crypto
> API" configuration knobs that seem to never be touched in practice.
I don't think finer grained control is necessary.
The tristate is the best possible interface for the people running
precompiled distribution kernels. Ideally, deactivating the restriction
should also be disallowed in lockdown mode -- and this becomes a lot
easier to subvert if the list of algorithms is runtime configurable.
I think it is safe to assume that the people using AF_ALG with hardware
crypto engines are building embedded systems with a custom kernel
configuration, so the .config is probably the best place for the
selection of algorithms that should remain available in restricted mode.
Simon
^ permalink raw reply
* Re: [PATCH v5 06/24] sched/core: allow only preferred CPUs in is_cpu_allowed
From: Yury Norov @ 2026-06-29 4:09 UTC (permalink / raw)
To: Shrikanth Hegde
Cc: Yury Norov, linux-kernel, mingo, peterz, juri.lelli,
vincent.guittot, kprateek.nayak, iii, corbet, tglx, gregkh,
pbonzini, seanjc, vschneid, huschle, rostedt, dietmar.eggemann,
maddy, srikar, hdanton, chleroy, vineeth, frederic, arighi, pauld,
christian.loehle, tj, tommaso.cucinotta, maz, rafael, rdunlap,
kernellwp, linux-doc
In-Reply-To: <1ace8847-db42-49a8-8d0f-6eeead1c360f@linux.ibm.com>
On Sat, Jun 27, 2026 at 12:13:49AM +0530, Shrikanth Hegde wrote:
> Hi Yury.
>
> On 6/26/26 6:55 PM, Shrikanth Hegde wrote:
> > Hi Yury. Thanks for going through the patches.
> >
>
> [...]
>
> > > So, you've got 3 options to declare the status: self-explaining enum,
> > > self-explaining #defines, and this random numbers explained in
> > > comment. The latter option is the worst to me.
> >
> > ok. I will define the enums.
> >
> > >
> > > And you didn't provide any benchmark advocating this caching
> > > optimization.
>
>
> I did below to see. Made interval as 100ms.
> Ran ./hackbench 30 process 30000 loops in both the VM at the same time.
> Values are average of 5 runs.
>
> With optimization:
> 13.6 seconds
>
> Without optimization:
> 13.8 seconds
And what's the p-value for them?
...
> > If we move to local variable then this won;t be necessary,
> > just enum's would be enough (I think). Let me go stare at it.
>
> I have made it use the local variable instead. There maybe better names
> for variable, put something quickly to check the idea.
> Effectively this PATCH 6 becomes:
>
> Does this seems better?
> Please let me know your comments.
I think, the below is too massive change for optimization of an
optimization for a particular, not too common config. And the whole
improvement is ~1%, assuming it's statistically important...
Just as said on previous round. Please order your series such that the
core logic goes first, and all sorts of complications, like this
optimization, are appended at the end.
> ---
>
> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
> index 9e16946c9d62..fafedd52611f 100644
> --- a/kernel/sched/core.c
> +++ b/kernel/sched/core.c
> @@ -2498,8 +2498,10 @@ static inline bool rq_has_pinned_tasks(struct rq *rq)
> * Per-CPU kthreads are allowed to run on !active && online CPUs, see
> * __set_cpus_allowed_ptr() and select_fallback_rq().
> */
> -static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
> +static inline bool is_cpu_allowed(struct task_struct *p, int cpu, int cached)
> {
> + bool task_check_preferred_cpu;
> +
> /* When not in the task's cpumask, no point in looking further. */
> if (!task_allowed_on_cpu(p, cpu))
> return false;
> @@ -2508,9 +2510,24 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
> if (is_migration_disabled(p))
> return cpu_online(cpu);
> + /*
> + * This is essential to maintain user affinities when preferred
> + * CPUs change. A task pinned on non-preferred CPU should continue
> + * to run there, since this is non-user triggered.
> + *
> + * If CPU is non-preferred and task can run on other CPUs which are
> + * currently preferred, then choose those other CPUs instead.
> + * Overhead is minimal when CPU is preferred.
> + */
> + task_check_preferred_cpu = !cpu_preferred(cpu) &&
> + task_has_preferred_cpus(p, cached);
> +
> /* Non kernel threads are not allowed during either online or offline. */
> - if (!(p->flags & PF_KTHREAD))
> + if (!(p->flags & PF_KTHREAD)) {
> + if (task_check_preferred_cpu)
> + return false;
> return cpu_active(cpu);
> + }
> /* KTHREAD_IS_PER_CPU is always allowed. */
> if (kthread_is_per_cpu(p))
> @@ -2520,6 +2537,10 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
> if (cpu_dying(cpu))
> return false;
> + /* Try on preferred CPU first if possible*/
> + if (task_check_preferred_cpu)
> + return false;
> +
> /* But are allowed during online. */
> return cpu_online(cpu);
> }
> @@ -2595,7 +2616,7 @@ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
> __must_hold(__rq_lockp(rq))
> {
> /* Affinity changed (again). */
> - if (!is_cpu_allowed(p, dest_cpu))
> + if (!is_cpu_allowed(p, dest_cpu, NO_CACHED_VAL))
> return rq;
This thing I really dislike. The unrelated code should not be
affected. You can make it less visually invasive with:
#define is_cpu_allowed(p, cpu) __is_cpu_allowed(p, cpu, NO_CACHED_VAL)
Please reconsider your code to have the changes better localized.
Thanks,
Yury
> rq = move_queued_task(rq, rf, p, dest_cpu);
> @@ -3547,7 +3568,15 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
> int nid = cpu_to_node(cpu);
> const struct cpumask *nodemask = NULL;
> enum { cpuset, possible, fail } state = cpuset;
> - int dest_cpu;
> + int dest_cpu, has_preferred_cpu;
> +
> + /*
> + * Cache the value whether task's affinity spans preferred CPUs.
> + * This helps to avoid repeating the same for each CPU
> + * later in the loop.
> + */
> + has_preferred_cpu = task_has_preferred_cpus(p, NO_CACHED_VAL) ?
> + TASK_HAS_PREFERRED_CPUS : TASK_NO_PREFERRED_CPUS;
> /*
> * If the node that the CPU is on has been offlined, cpu_to_node()
> @@ -3559,7 +3588,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
> /* Look for allowed, online CPU in same node. */
> for_each_cpu(dest_cpu, nodemask) {
> - if (is_cpu_allowed(p, dest_cpu))
> + if (is_cpu_allowed(p, dest_cpu, has_preferred_cpu))
> return dest_cpu;
> }
> }
> @@ -3567,7 +3596,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
> for (;;) {
> /* Any allowed, online CPU? */
> for_each_cpu(dest_cpu, p->cpus_ptr) {
> - if (!is_cpu_allowed(p, dest_cpu))
> + if (!is_cpu_allowed(p, dest_cpu, has_preferred_cpu))
> continue;
> goto out;
> @@ -3632,7 +3661,7 @@ int select_task_rq(struct task_struct *p, int cpu, int *wake_flags)
> * [ this allows ->select_task() to simply return task_cpu(p) and
> * not worry about this generic constraint ]
> */
> - if (unlikely(!is_cpu_allowed(p, cpu)))
> + if (unlikely(!is_cpu_allowed(p, cpu, NO_CACHED_VAL)))
> cpu = select_fallback_rq(task_cpu(p), p);
> return cpu;
> @@ -6467,7 +6496,7 @@ static bool try_steal_cookie(int this, int that)
> if (p == src->core_pick || p == src->curr)
> goto next;
> - if (!is_cpu_allowed(p, this))
> + if (!is_cpu_allowed(p, this, NO_CACHED_VAL))
> goto next;
> if (p->core_occupation > dst->idle->core_occupation)
> diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
> index c7c2dea65edd..949c044702c1 100644
> --- a/kernel/sched/sched.h
> +++ b/kernel/sched/sched.h
> @@ -4213,4 +4213,32 @@ DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
> #include "ext.h"
> +enum task_preferred_cached {
> + TASK_NO_PREFERRED_CPUS = -1,
> + NO_CACHED_VAL,
> + TASK_HAS_PREFERRED_CPUS,
> +};
> +
> +/*
> + * Value is cached when called via select_fallback_rq().
> + *
> + * TASK_NO_PREFERRED_CPUS : Cached and preferred CPUs exists in task's
> + * affinity.
> + * NO_CACHED_VAL: Not cached and need to evaluate.
> + * TASK_HAS_PREFERRED_CPUS: Cached and preferred CPU doesn't exits
> + * task's affinity
> + *
> + * Only affects FAIR task.
> + */
> +static inline bool task_has_preferred_cpus(struct task_struct *p, int cached)
> +{
> + /* Only FAIR tasks honor preferred CPU state */
> + if (unlikely(p->sched_class != &fair_sched_class))
> + return false;
> +
> + if (cached)
> + return cached > 0;
> + else
> + return cpumask_intersects(p->cpus_ptr, cpu_preferred_mask);
> +}
> #endif /* _KERNEL_SCHED_SCHED_H */
^ permalink raw reply
* Re: [PATCH v5 06/24] sched/core: allow only preferred CPUs in is_cpu_allowed
From: Shrikanth Hegde @ 2026-06-29 4:14 UTC (permalink / raw)
To: Yury Norov
Cc: linux-kernel, mingo, peterz, juri.lelli, vincent.guittot,
kprateek.nayak, iii, corbet, tglx, gregkh, pbonzini, seanjc,
vschneid, huschle, rostedt, dietmar.eggemann, maddy, srikar,
hdanton, chleroy, vineeth, frederic, arighi, pauld,
christian.loehle, tj, tommaso.cucinotta, maz, rafael, rdunlap,
kernellwp, linux-doc
In-Reply-To: <akHv_4l0izJb6TgZ@yury>
Hi Yury.
On 6/29/26 9:39 AM, Yury Norov wrote:
> On Sat, Jun 27, 2026 at 12:13:49AM +0530, Shrikanth Hegde wrote:
>> Hi Yury.
>>
>> On 6/26/26 6:55 PM, Shrikanth Hegde wrote:
>>> Hi Yury. Thanks for going through the patches.
>>>
>>
>> [...]
>>
>>>> So, you've got 3 options to declare the status: self-explaining enum,
>>>> self-explaining #defines, and this random numbers explained in
>>>> comment. The latter option is the worst to me.
>>>
>>> ok. I will define the enums.
>>>
>>>>
>>>> And you didn't provide any benchmark advocating this caching
>>>> optimization.
>>
>>
>> I did below to see. Made interval as 100ms.
>> Ran ./hackbench 30 process 30000 loops in both the VM at the same time.
>> Values are average of 5 runs.
>>
>> With optimization:
>> 13.6 seconds
>>
>> Without optimization:
>> 13.8 seconds
>
> And what's the p-value for them?
>
> ...
>
>>> If we move to local variable then this won;t be necessary,
>>> just enum's would be enough (I think). Let me go stare at it.
>>
>> I have made it use the local variable instead. There maybe better names
>> for variable, put something quickly to check the idea.
>> Effectively this PATCH 6 becomes:
>>
>> Does this seems better?
>> Please let me know your comments.
>
> I think, the below is too massive change for optimization of an
> optimization for a particular, not too common config. And the whole
> improvement is ~1%, assuming it's statistically important...
>
> Just as said on previous round. Please order your series such that the
> core logic goes first, and all sorts of complications, like this
> optimization, are appended at the end.
Ok. I will split it up into two patches.
One without any optimization but with comment explaining the rare case of N**2.
Second one at the end of the series, with a patch do the optimization.
>
>> ---
>>
>> diff --git a/kernel/sched/core.c b/kernel/sched/core.c
>> index 9e16946c9d62..fafedd52611f 100644
>> --- a/kernel/sched/core.c
>> +++ b/kernel/sched/core.c
>> @@ -2498,8 +2498,10 @@ static inline bool rq_has_pinned_tasks(struct rq *rq)
>> * Per-CPU kthreads are allowed to run on !active && online CPUs, see
>> * __set_cpus_allowed_ptr() and select_fallback_rq().
>> */
>> -static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
>> +static inline bool is_cpu_allowed(struct task_struct *p, int cpu, int cached)
>> {
>> + bool task_check_preferred_cpu;
>> +
>> /* When not in the task's cpumask, no point in looking further. */
>> if (!task_allowed_on_cpu(p, cpu))
>> return false;
>> @@ -2508,9 +2510,24 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
>> if (is_migration_disabled(p))
>> return cpu_online(cpu);
>> + /*
>> + * This is essential to maintain user affinities when preferred
>> + * CPUs change. A task pinned on non-preferred CPU should continue
>> + * to run there, since this is non-user triggered.
>> + *
>> + * If CPU is non-preferred and task can run on other CPUs which are
>> + * currently preferred, then choose those other CPUs instead.
>> + * Overhead is minimal when CPU is preferred.
>> + */
>> + task_check_preferred_cpu = !cpu_preferred(cpu) &&
>> + task_has_preferred_cpus(p, cached);
>> +
>> /* Non kernel threads are not allowed during either online or offline. */
>> - if (!(p->flags & PF_KTHREAD))
>> + if (!(p->flags & PF_KTHREAD)) {
>> + if (task_check_preferred_cpu)
>> + return false;
>> return cpu_active(cpu);
>> + }
>> /* KTHREAD_IS_PER_CPU is always allowed. */
>> if (kthread_is_per_cpu(p))
>> @@ -2520,6 +2537,10 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
>> if (cpu_dying(cpu))
>> return false;
>> + /* Try on preferred CPU first if possible*/
>> + if (task_check_preferred_cpu)
>> + return false;
>> +
>> /* But are allowed during online. */
>> return cpu_online(cpu);
>> }
>> @@ -2595,7 +2616,7 @@ static struct rq *__migrate_task(struct rq *rq, struct rq_flags *rf,
>> __must_hold(__rq_lockp(rq))
>> {
>> /* Affinity changed (again). */
>> - if (!is_cpu_allowed(p, dest_cpu))
>> + if (!is_cpu_allowed(p, dest_cpu, NO_CACHED_VAL))
>> return rq;
>
> This thing I really dislike. The unrelated code should not be
> affected. You can make it less visually invasive with:
>
> #define is_cpu_allowed(p, cpu) __is_cpu_allowed(p, cpu, NO_CACHED_VAL)
>
> Please reconsider your code to have the changes better localized.
>
> Thanks,
> Yury
>
That was typed out too fast. I did refactor something like that later.
But i will split this into twp patches as said above.
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 9e16946c9d62..a1b21c21aa9c 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -2498,8 +2498,11 @@ static inline bool rq_has_pinned_tasks(struct rq *rq)
* Per-CPU kthreads are allowed to run on !active && online CPUs, see
* __set_cpus_allowed_ptr() and select_fallback_rq().
*/
-static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
+static inline bool __is_cpu_allowed(struct task_struct *p, int cpu,
+ int pref_state)
{
+ bool task_check_preferred_cpu;
+
/* When not in the task's cpumask, no point in looking further. */
if (!task_allowed_on_cpu(p, cpu))
return false;
@@ -2508,9 +2511,24 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
if (is_migration_disabled(p))
return cpu_online(cpu);
+ /*
+ * This is essential to maintain user affinities when preferred
+ * CPUs change. A task pinned on non-preferred CPU should continue
+ * to run there, since this is non-user triggered.
+ *
+ * If CPU is non-preferred and task can run on other CPUs which are
+ * currently preferred, then choose those other CPUs instead.
+ * Overhead is minimal when CPU is preferred.
+ */
+ task_check_preferred_cpu = !cpu_preferred(cpu) &&
+ task_has_preferred_cpus(p, pref_state);
+
/* Non kernel threads are not allowed during either online or offline. */
- if (!(p->flags & PF_KTHREAD))
+ if (!(p->flags & PF_KTHREAD)) {
+ if (task_check_preferred_cpu)
+ return false;
return cpu_active(cpu);
+ }
/* KTHREAD_IS_PER_CPU is always allowed. */
if (kthread_is_per_cpu(p))
@@ -2520,10 +2538,19 @@ static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
if (cpu_dying(cpu))
return false;
+ /* Try on preferred CPU first if possible*/
+ if (task_check_preferred_cpu)
+ return false;
+
/* But are allowed during online. */
return cpu_online(cpu);
}
+static inline bool is_cpu_allowed(struct task_struct *p, int cpu)
+{
+ return __is_cpu_allowed(p, cpu, PREFERRED_CPU_UNKNOWN);
+}
+
/*
* This is how migration works:
*
@@ -3547,7 +3574,15 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
int nid = cpu_to_node(cpu);
const struct cpumask *nodemask = NULL;
enum { cpuset, possible, fail } state = cpuset;
- int dest_cpu;
+ int dest_cpu, pref_state;
+
+ /*
+ * Cache the value whether task's affinity spans preferred CPUs.
+ * This helps to avoid repeating the same for each CPU
+ * later in the loop.
+ */
+ pref_state = task_has_preferred_cpus(p, PREFERRED_CPU_UNKNOWN) ?
+ PREFERRED_CPU_EXISTS : PREFERRED_CPU_NONE;
/*
* If the node that the CPU is on has been offlined, cpu_to_node()
@@ -3559,7 +3594,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
/* Look for allowed, online CPU in same node. */
for_each_cpu(dest_cpu, nodemask) {
- if (is_cpu_allowed(p, dest_cpu))
+ if (__is_cpu_allowed(p, dest_cpu, pref_state))
return dest_cpu;
}
}
@@ -3567,7 +3602,7 @@ static int select_fallback_rq(int cpu, struct task_struct *p)
for (;;) {
/* Any allowed, online CPU? */
for_each_cpu(dest_cpu, p->cpus_ptr) {
- if (!is_cpu_allowed(p, dest_cpu))
+ if (!__is_cpu_allowed(p, dest_cpu, pref_state))
continue;
goto out;
diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h
index c7c2dea65edd..6a352d235503 100644
--- a/kernel/sched/sched.h
+++ b/kernel/sched/sched.h
@@ -4213,4 +4213,33 @@ DEFINE_CLASS_IS_UNCONDITIONAL(sched_change)
#include "ext.h"
+/*
+ * PREFERRED_CPU_UNKNOWN: Unknown and need to evaluate.
+ * PREFERRED_CPU_NONE : Known and No preferred CPUs exists in task's affinity.
+ * PREFERRED_CPU_EXISTS: Known and preferred CPU exists in task's affinity.
+ */
+
+enum task_preferred_cached {
+ PREFERRED_CPU_UNKNOWN,
+ PREFERRED_CPU_NONE,
+ PREFERRED_CPU_EXISTS,
+};
+
+/*
+ * Value is known when called via select_fallback_rq(). This helps to
+ * avoid calling cpumask_intersects repeatedly in the loop.
+ *
+ * Only affects FAIR task.
+ */
+static inline bool task_has_preferred_cpus(struct task_struct *p, int pref_state)
+{
+ /* Only FAIR tasks honor preferred CPU state */
+ if (unlikely(p->sched_class != &fair_sched_class))
+ return false;
+
+ if (pref_state != PREFERRED_CPU_UNKNOWN)
+ return pref_state == PREFERRED_CPU_EXISTS;
+
+ return cpumask_intersects(p->cpus_ptr, cpu_preferred_mask);
+}
#endif /* _KERNEL_SCHED_SCHED_H */
^ permalink raw reply related
* Re: [PATCH] Documentation/bpf: make it clear that kfuncs should be non-static
From: Yonghong Song @ 2026-06-29 4:38 UTC (permalink / raw)
To: JP Kobryn, ast, roman.gushchin, daniel, andrii, eddyz87, memxor,
martin.lau, song, jolsa, emil, corbet, skhan, bpf
Cc: linux-doc, linux-kernel
In-Reply-To: <20260626172026.7327-1-jp.kobryn@linux.dev>
On 6/26/26 10:20 AM, JP Kobryn wrote:
> The kfunc documentation mentions how the macro __bpf_kfunc prevents
> inlining for static functions. This makes it sound like static kfuncs are
> acceptable. Although static kfuncs may happen to work, it is by chance that
> the compiler chose not to rename these functions and BTF resolution still
> succeeds.
>
> Make it clear in the documentation why kfuncs should not be declared
> static. First, remove wording that makes it sound like static is ok. Then
> point out the external naming needed for BTF resolution. Finally point out
> that sparse may warn on unreferenced kfuncs and that this warning can be
> ignored.
>
> Signed-off-by: JP Kobryn <jp.kobryn@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
> ---
> Documentation/bpf/kfuncs.rst | 21 ++++++++++++++-------
> 1 file changed, 14 insertions(+), 7 deletions(-)
>
> diff --git a/Documentation/bpf/kfuncs.rst b/Documentation/bpf/kfuncs.rst
> index 4c814ff6061e..1dbaff8d4805 100644
> --- a/Documentation/bpf/kfuncs.rst
> +++ b/Documentation/bpf/kfuncs.rst
> @@ -276,19 +276,26 @@ This set encodes the BTF ID of each kfunc listed above, and encodes the flags
> along with it. Ofcourse, it is also allowed to specify no flags.
>
> kfunc definitions should also always be annotated with the ``__bpf_kfunc``
> -macro. This prevents issues such as the compiler inlining the kfunc if it's a
> -static kernel function, or the function being elided in an LTO build as it's
> -not used in the rest of the kernel. Developers should not manually add
> -annotations to their kfunc to prevent these issues. If an annotation is
> -required to prevent such an issue with your kfunc, it is a bug and should be
> -added to the definition of the macro so that other kfuncs are similarly
> -protected. An example is given below::
> +macro. This prevents issues such as the compiler inlining the kfunc, or the
> +function being elided in an LTO build as it's not used in the rest of the
> +kernel. Developers should not manually add annotations to their kfunc to prevent
> +these issues. If an annotation is required to prevent such an issue with your
> +kfunc, it is a bug and should be added to the definition of the macro so that
> +other kfuncs are similarly protected. An example is given below::
>
> __bpf_kfunc struct task_struct *bpf_get_task_pid(s32 pid)
> {
> ...
> }
>
> +Note that kfuncs must not be declared ``static``. A kfunc can be called from a
> +BPF program ``*.c`` file outside the compilation unit that defines it, so its
> +externally visible name must remain available for BTF ID lookup. ``static``
> +linkage allows the compiler to rename the function, which can break this
> +BTF-based kfunc resolution. Further note that sparse may warn that an otherwise
> +unreferenced kfunc should be static. Such warnings should be ignored for kfunc
> +definitions.
> +
> 2.5.1 KF_ACQUIRE flag
> ---------------------
>
^ permalink raw reply
* Re: [PATCH v1] docs/ja_JP: translate submitting-patches.rst (sign-off)
From: Akira Yokosawa @ 2026-06-29 5:16 UTC (permalink / raw)
To: Akiyoshi Kurita, linux-doc; +Cc: linux-kernel, corbet, Akira Yokosawa
In-Reply-To: <20260613233541.50732-1-weibu@redadmin.org>
Hi,
I'm sorry I couldn't respond promptly.
On Sun, 14 Jun 2026 08:35:41 +0900, Akiyoshi Kurita wrote:
> Translate the "Include PATCH in the subject" and "Sign your work -
> the Developer's Certificate of Origin" sections in
> Documentation/translations/ja_JP/process/submitting-patches.rst.
>
> Keep the wording close to the English text and wrap lines to match
> the style used in the surrounding Japanese translation.
>
> Signed-off-by: Akiyoshi Kurita <weibu@redadmin.org>
> ---
> .../ja_JP/process/submitting-patches.rst | 70 +++++++++++++++++++
> 1 file changed, 70 insertions(+)
>
> diff --git a/Documentation/translations/ja_JP/process/submitting-patches.rst b/Documentation/translations/ja_JP/process/submitting-patches.rst
> index d31d469909e4..56494bac169c 100644
> --- a/Documentation/translations/ja_JP/process/submitting-patches.rst
> +++ b/Documentation/translations/ja_JP/process/submitting-patches.rst
> @@ -402,3 +402,73 @@ ping したりする前に、少なくとも 1 週間は待ってください。
> パッチまたはパッチシリーズの修正版を投稿する場合は、"RESEND" を
> 追加しないでください。"RESEND" は、前回の投稿から一切変更していない
> パッチまたはパッチシリーズを再送する場合にのみ使います。
> +
> +
> +件名に PATCH を含める
> +----------------------
> +
> +Linus と linux-kernel には大量のメールが届くため、メールの件名の
> +先頭に ``[PATCH]`` を付けるのが一般的な慣例です。これにより、
> +Linus や他のカーネル開発者は、パッチを他のメール議論からより
> +簡単に区別できるようになります。
> +
> +``git send-email`` は、これを自動的に行ってくれます。
> +
> +
> +自分の作業に署名する - Developer's Certificate of Origin
> +---------------------------------------------------------
> +
> +誰が何を行ったのかを追跡しやすくするため、特に、複数階層の
> +メンテナを経由して、最終的にカーネル内のあるべき場所へたどり着く
> +可能性があるパッチについて、メールでやり取りされるパッチに
> +``sign-off`` 手続きを導入しています。
> +
> +``sign-off`` は、パッチ説明の末尾に置く単純な 1 行です。これは、
> +あなたがそのパッチを書いたこと、またはオープンソースのパッチとして
> +渡す権利を持っていることを証明するものです。ルールは非常に単純です。
> +以下を証明できるなら:
> +
> +Developer's Certificate of Origin 1.1
> +^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
You are keeping this title untranslated.
I agree it is not easy. I even think it is close to impossible.
But then, I don't see much point in translating the "certificate"
itself.
> +
> +このプロジェクトへ貢献することにより、私は以下を証明します:
> +
> + (a) この貢献は、全部または一部を私が作成したものであり、
> + ファイルに示されているオープンソースライセンスの下で
> + 提出する権利を私が持っていること。または、
> +
> + (b) この貢献は、私の知る限り、適切なオープンソース
> + ライセンスの下にある過去の成果物に基づくものであり、
> + そのライセンスの下で、その成果物を、全部または一部を
> + 私が作成した修正とともに、同じオープンソースライセンスの
> + 下で提出する権利を私が持っていること。ただし、
> + ファイルに示されているように、異なるライセンスでの提出が
> + 許可されている場合を除きます。または、
> +
> + (c) この貢献は、(a)、(b)、または (c) を証明した別の人物から
> + 直接私に提供されたものであり、私はそれを変更していないこと。
> +
> + (d) このプロジェクトと貢献が公開されること、ならびに、
> + 貢献の記録（私が提出したすべての個人情報、私の sign-off を
> + 含む）が無期限に維持され、このプロジェクトまたは関係する
> + オープンソースライセンスに従って再配布される可能性がある
> + ことを、私は理解し同意します。
What you need to agree in signing off is the English certificate.
Not the translated one. So this can confuse people.
I don't have any good idea.
Please convince me you can translate the certificate
without any concern of confusion.
> +
> +その場合は、次のような行を追加するだけです::
> +
> + Signed-off-by: Random J Developer <random@developer.example.org>
> +
> +確認可能な身元情報を使ってください（残念ながら、匿名での貢献は
> +受け付けられません）。これは ``git commit -s`` を使えば自動的に
> +行われます。Revert パッチにも ``Signed-off-by`` を含めるべきです。
> +``git revert -s`` はこれを自動的に行ってくれます。
> +
> +パッチ末尾に追加のタグを付ける人もいます。それらは今のところ単に
> +無視されますが、社内手続きを示したり、sign-off に関する特別な
> +詳細を示したりするために使うことはできます。
> +
> +作者の SoB に続くそれ以降の SoB (Signed-off-by:) は、パッチを
> +取り扱い、次へ受け渡した人々によるものですが、その開発に関与した
> +ことを意味しません。SoB の連鎖は、パッチがメンテナへ伝わり、
> +最終的に Linus へ届くまでに実際にたどった **本当の** 経路を
> +反映すべきです。先頭の SoB エントリは、単独の主たる作者を示します。
I think organization of this section in English version was
corrupted during reST conversion. I'll submit a fix.
Regards,
Akira
^ permalink raw reply
* Re: [PATCH net-deletions] net: remove ax25 and amateur radio (hamradio) subsystem
From: Jiri Slaby @ 2026-06-29 5:24 UTC (permalink / raw)
To: Jakub Kicinski, davem
Cc: netdev, edumazet, pabeni, andrew+netdev, horms, corbet, skhan,
federico.vaga, carlos.bilbao, avadhut.naik, alexs, si.yanteng,
dzm91, 2023002089, tsbogend, dsahern, jani.nikula, mchehab+huawei,
gregkh, tytso, herbert, ebiggers, johannes.berg, geert, pablo,
tglx, mashiro.chen, mingo, dqfext, jreuter, sdf, pkshih,
enelsonmoore, mkl, toke, kees, crossd, jlayton, wangliang74,
aha310510, takamitz, kuniyu, linux-doc, linux-mips
In-Reply-To: <0883a8e0-e8b4-4f22-bfc6-dd4a0fcf8b7a@kernel.org>
On 27. 06. 26, 21:04, Jiri Slaby wrote:
> On 21. 04. 26, 4:18, Jakub Kicinski wrote:
>> Remove the amateur radio (AX.25, NET/ROM, ROSE) protocol implementation
>> and all associated hamradio device drivers from the kernel tree.
>> This set of protocols has long been a huge bug/syzbot magnet,
>> and since nobody stepped up to help us deal with the influx
>> of the AI-generated bug reports we need to move it out of tree
>> to protect our sanity.
>>
>> The code is moved to an out-of-tree repo:
>> https://github.com/linux-netdev/mod-orphan
>> if it's cleaned up and reworked there we can accept it back.
>>
>> Minimal stub headers are kept for include/net/ax25.h (AX25_P_IP,
>> AX25_ADDR_LEN, ax25_address) and include/net/rose.h (ROSE_ADDR_LEN)
>> so that the conditional integration code in arp.c and tun.c continues
>> to compile and work when the out-of-tree modules are loaded.
> ...
>> delete mode 100644 include/uapi/linux/scc.h
> Unfortunately, this broke builds of LLVM -- compiler-rt in particular
> (and GCC builds allegedly too). They dropped the include and its use
> [1], but IMO we should keep the uapi header with those two structs
> (scc_modem + scc_stat) for some time.
>
> [1] https://github.com/llvm/llvm-project/
> commit/3dc4fd6dd41100f051a63642f449b16324389c96
And net-tools are broken by the uapi/linux/rose.h removal:
rose.c:39:10: fatal error: linux/rose.h: No such file or directory
at:
https://github.com/ecki/net-tools/blob/2ab3c5efdb5c220bc9a649fded56c361136bff1a/lib/rose.c#L39
>
> thanks,
--
js
suse labs
^ permalink raw reply
* Re: [PATCH v2] usbcore: Add quirk for 255-bytes initial config read
From: Nikhil Solanke @ 2026-06-29 5:30 UTC (permalink / raw)
To: Michal Pecio
Cc: linux-usb, gregkh, linux-kernel, stern, stable, corbet, skhan,
linux-doc
In-Reply-To: <20260628231634.6752f74d.michal.pecio@gmail.com>
> And here it's USB_QUIRK_WINDOWS_CONFIG_REQ_SIZE, but in the commit
> message it was USB_QUIRK_CONFIG_SIZE.
Yes, I have fixed it already.
> Honestly, I would suggest a third option: something with "255" instead
> of "Windows", because not everybody knows how windows queries
> descriptors, but everybody knows what 255 is.
Well naming ain't my strong suit (if I name something, it will
definitely get called out). Do you have a specific name in mind? if
your concern lies more in people not knowing what Windows does, should
i just make it apparent in a comment where it is set?
> That's a lot of capital letters, USBCONFIG_WINDOWS_REQ_SIZE never
> appears outside this function and personally I would just spell it out
> as 255 here with appropriate comment.
I wanted to avoid the plausible "avoid magic numbers" criticism. If
everybody else is fine with bare 255, I will just do that then.
> > + bigbuffer = (unsigned char *) desc;
> > + desc = NULL;
>
> What happens in the next iteration of the loop?
Disaster to say the least. A memcpy in bigbuffer and memset(0,..) on
desc would be the correct approach here, wouldn't it?
On that note, I discovered that usb_get_descriptor just blindly trusts
the caller with the allocation of buf, it never checks if buf is null
or not. There is only a check for the size. and then there is a
memset(buf, 0, size). This results in a segfault if buf is NULL and
size > 0. Perhaps it's time for a new patch to fix this?
> I wonder if it wouldn't make sense to split announce_device() so that
> the first line is printed as soon as usb_new_device() starts, before
> enumeration is attempted and possibly fails.
Do you want something like announce_device_ids() where it would only
print out the first "New Usb device found..." line? and then
announce_device_strings()?
Perhaps even another macro announce_device that does both? But its
only used in one place, so I doubt it would be necessary.
> That would be a separate patch, of course.
If i have to make this change, should this be a completely separate
patch or is it fine to include it in this patchseries?
Thanks,
Nikhil Solanke
^ permalink raw reply
* [PATCH v3] cgroup/cpu: document cpu.stat.local and clarify cpu.stat behavior
From: Sun Shaojie @ 2026-06-29 6:06 UTC (permalink / raw)
To: mkoutny
Cc: cgroups, corbet, cui.tao, hannes, linux-doc, linux-kernel, skhan,
sunshaojie, tj
In-Reply-To: <aj6PQPz4IDoVTnPL@localhost.localdomain>
Add documentation for the cpu.stat.local interface file, which reports
the throttled_usec stat -- the actual throttling time incurred by the
cgroup's own runqueues, which may include throttling inherited from
ancestor cgroup bandwidth limits. Unlike cpu.stat's throttled_usec
which only accounts for throttling caused by the cgroup's own CFS
bandwidth limit.
When the controller is not enabled, the stat is not reported.
Also clarify cpu.stat descriptions: note that the three base CPU usage
stats (usage_usec, user_usec, system_usec) include descendant cgroups,
and that the five CFS bandwidth stats are non-hierarchical -- they only
account for throttling caused by the cgroup's own bandwidth limit.
Signed-off-by: Sun Shaojie <sunshaojie@kylinos.cn>
---
Changes in v3:
- Clarify that the three base CPU usage stats include descendant
cgroups.
- Add a note explaining that the five CFS bandwidth stats are
non-hierarchical.
---
Documentation/admin-guide/cgroup-v2.rst | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
diff --git a/Documentation/admin-guide/cgroup-v2.rst b/Documentation/admin-guide/cgroup-v2.rst
index 993446ab66d0..91ad91680cf0 100644
--- a/Documentation/admin-guide/cgroup-v2.rst
+++ b/Documentation/admin-guide/cgroup-v2.rst
@@ -1145,7 +1145,7 @@ will be referred to. All time durations are in microseconds.
This file exists whether the controller is enabled or not.
It always reports the following three stats, which account for all the
- processes in the cgroup:
+ processes in the cgroup (including those in descendant cgroups):
- usage_usec
- user_usec
@@ -1160,6 +1160,27 @@ will be referred to. All time durations are in microseconds.
- nr_bursts
- burst_usec
+ Note that the above five CFS bandwidth stats are non-hierarchical;
+ they only account for throttling caused by this cgroup's own bandwidth
+ limit, not including throttling inherited from ancestor cgroups.
+
+ cpu.stat.local
+ A read-only flat-keyed file.
+ This file exists whether the controller is enabled or not.
+
+ It reports the following stat when the controller is enabled:
+
+ - throttled_usec
+
+ Unlike the ``throttled_usec`` reported by ``cpu.stat`` which
+ accounts for throttling caused by this cgroup's own CFS
+ bandwidth limit, ``cpu.stat.local`` reports the actual
+ throttling time incurred by this cgroup's own runqueues,
+ which may include throttling inherited from ancestor
+ cgroup bandwidth limits.
+
+ When the controller is not enabled, this stat is not reported.
+
cpu.weight
A read-write single value file which exists on non-root
cgroups. The default is "100".
--
2.25.1
^ permalink raw reply related
* [PATCH v13 00/11] tracing/probes: Add more typecast features
From: Masami Hiramatsu (Google) @ 2026-06-29 6:12 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
Hi,
Here is the 13th version of series to introduce more typecast features
to probe events. The previous version is here:
https://lore.kernel.org/all/178269068329.1161310.17763177188897860801.stgit@devnote2/
This version fixes a missed comma issue [8/11][10/11] pointed
by Sashiko.
This series extends BTF typecast feature and add more options:
1. Expanding BTF typecast to kprobe and fprobe.
(currently only function entry/exit)
2. Introduce container_of like typecast. This adds a "assigned
member" option to the typecast.
(STRUCT,MEMBER)VAR->ANOTHER_MEMBER
This casts VAR to STRUCT type but the VAR is as the address
of STRUCT.MEMBER. In C, it is:
container_of(VAR, STRUCT, MEMBER)->ANOTHER_MEMBER
3. Support nested typecast, e.g.
(STRUCT)((STRUCT2)VAR->MEMBER2)->MEMBER
the nest level must be smaller than 3.
4. Add $current variable to point "current" task_struct.
This is useful with typecast, e.g.
(task_struct)$current->pid
5. per-cpu dereference support.
Intrdouce this_cpu_read(VAR) and this_cpu_ptr(VAR) to
access per-cpu data on the current CPU (accessing other CPU
data is not stable, because it can be changed.)
You can access the member of per-cpu data structure using
typecast like:
(STRUCT)this_cpu_ptr(VAR)->MEMBER
6. Support event fields without $ prefix on eprobes.
Now eprobe events can access its event fields.
And added fetcharg dump feature (for debug) and updated test scripts
to test part of them.
Thanks,
---
base-commit: c69b5f959286395e94c237ce6d7d4970bad7f6e3
Masami Hiramatsu (Google) (11):
tracing/probes: Allow eprobe to use variable without $ prefix
tracing/probes: Support dumping fetcharg program for debugging dynamic events
tools/bootconfig: Ignore comment lines in dynamic_events/kprobe_events file
perf/probe: Ignore comment lines in dynamic_events/kprobe_events file
tracing/probes: Support typecast for various probe events
tracing/probes: Support nested typecast
tracing/probes: Type casting always involves nested calls
tracing/probes: Support field specifier option for typecast
tracing/probes: Add $current variable support
tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to fetcharg
tracing/probes: Add a new testcase for BTF typecasts
Documentation/trace/eprobetrace.rst | 7
Documentation/trace/fprobetrace.rst | 10
Documentation/trace/kprobetrace.rst | 11
kernel/trace/Kconfig | 12
kernel/trace/trace.c | 8
kernel/trace/trace_eprobe.c | 2
kernel/trace/trace_fprobe.c | 2
kernel/trace/trace_kprobe.c | 2
kernel/trace/trace_probe.c | 585 ++++++++++++++++----
kernel/trace/trace_probe.h | 100 ++-
kernel/trace/trace_probe_tmpl.h | 25 +
kernel/trace/trace_uprobe.c | 3
samples/trace_events/trace-events-sample.c | 40 +
samples/trace_events/trace-events-sample.h | 34 +
tools/bootconfig/scripts/ftrace2bconf.sh | 2
tools/perf/util/probe-file.c | 2
.../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++
.../test.d/dynevent/btf_typecast_accepted.tc | 103 ++++
.../test.d/dynevent/eprobes_syntax_errors.tc | 12
.../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 12
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 12
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5
22 files changed, 886 insertions(+), 154 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
--
Masami Hiramatsu (Google) <mhiramat@kernel.org>
^ permalink raw reply
* [PATCH v13 01/11] tracing/probes: Allow eprobe to use variable without $ prefix
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
The commit 69efd863a785 ("tracing/eprobes: Allow use of BTF names
to dereference pointers") allows eprobe to use event field without
"$" prefix when it is used with typecast, it is natual to allow it
without typecast.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v8:
- Newly added.
---
kernel/trace/trace_probe.c | 12 +++++++++++-
kernel/trace/trace_probe.h | 1 +
.../test.d/dynevent/eprobes_syntax_errors.tc | 3 +--
3 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 0da7c0b53ba7..2ce7d62471cb 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -1341,7 +1341,17 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
ret = handle_typecast(arg, pcode, end, ctx);
break;
default:
- if (isalpha(arg[0]) || arg[0] == '_') { /* BTF variable */
+ if (isalpha(arg[0]) || arg[0] == '_') {
+ /* BTF variable or event field*/
+ if (ctx->flags & TPARG_FL_TEVENT) {
+ ret = parse_trace_event(arg, *pcode, ctx);
+ if (ret < 0) {
+ trace_probe_log_err(ctx->offset,
+ NO_EVENT_FIELD);
+ return -EINVAL;
+ }
+ break;
+ }
if (!tparg_is_function_entry(ctx->flags) &&
!tparg_is_function_return(ctx->flags)) {
trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 40b53b5b58a9..2e0d8384ee5c 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -559,6 +559,7 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(NO_PTR_STRCT, "This is not a pointer to union/structure."), \
C(NOSUP_DAT_ARG, "Non pointer structure/union argument is not supported."),\
C(BAD_HYPHEN, "Failed to parse single hyphen. Forgot '>'?"), \
+ C(NO_EVENT_FIELD, "This event field is not found."), \
C(NO_BTF_FIELD, "This field is not found."), \
C(BAD_BTF_TID, "Failed to get BTF type info."),\
C(BAD_TYPE4STR, "This type does not fit for string."),\
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
index 2a680c086047..0e65e787e426 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
@@ -10,7 +10,7 @@ check_error() { # command-with-error-pos-by-^
check_error 'e ^a.' # NO_EVENT_INFO
check_error 'e ^.b' # NO_EVENT_INFO
check_error 'e ^a.b' # BAD_ATTACH_EVENT
-check_error 'e syscalls/sys_enter_openat ^foo' # BAD_ATTACH_ARG
+check_error 'e syscalls/sys_enter_openat ^foo' # NO_EVENT_FIELD
check_error 'e:^/bar syscalls/sys_enter_openat' # NO_GROUP_NAME
check_error 'e:^12345678901234567890123456789012345678901234567890123456789012345/bar syscalls/sys_enter_openat' # GROUP_TOO_LONG
@@ -19,7 +19,6 @@ check_error 'e:^ syscalls/sys_enter_openat' # NO_EVENT_NAME
check_error 'e:foo/^12345678901234567890123456789012345678901234567890123456789012345 syscalls/sys_enter_openat' # EVENT_TOO_LONG
check_error 'e:foo/^bar.1 syscalls/sys_enter_openat' # BAD_EVENT_NAME
-check_error 'e:foo/bar syscalls/sys_enter_openat arg=^dfd' # BAD_FETCH_ARG
check_error 'e:foo/bar syscalls/sys_enter_openat arg=^$foo' # BAD_ATTACH_ARG
if grep -q '<attached-group>\.<attached-event>.*\[if <filter>\]' README; then
^ permalink raw reply related
* [PATCH v13 02/11] tracing/probes: Support dumping fetcharg program for debugging dynamic events
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
For debugging probe events, it is helpful to verify the compiled
fetch instructions for each probe argument. This introduces a new
kernel config CONFIG_PROBE_EVENTS_DUMP_FETCHARG to decode the
instruction sequence of each argument and display it under a
commented line starting with '#' immediately following the dynamic
event definition (such as in dynamic_events, kprobe_events,
uprobe_events, etc.).
For example:
/sys/kernel/tracing # cat dynamic_events
p:kprobes/p_vfs_read_0 vfs_read arg1=+0(file):ustring arg2=%ax:x16
# arg1: ARG(0) -> ST_USTRING(offset=0,size=4) -> END
# arg2: REG(80) -> ST_RAW(size=2) -> END
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v8:
- State this feature is only for debugging probe events.
- Fix dependency list after description in Kconfig.
Changes in v7:
- Show trace event field name for FETCH_OP_TP_ARG.
- Show immediate string value for FETCH_OP_IMMSTR.
- Fix style issues warned by checkpatch.pl.
Changes in v6:
- Newly added.
---
kernel/trace/Kconfig | 12 +++++
kernel/trace/trace_eprobe.c | 2 +
kernel/trace/trace_fprobe.c | 2 +
kernel/trace/trace_kprobe.c | 2 +
kernel/trace/trace_probe.c | 96 +++++++++++++++++++++++++++++++++++++++++++
kernel/trace/trace_probe.h | 79 +++++++++++++++++++++--------------
kernel/trace/trace_uprobe.c | 3 +
7 files changed, 164 insertions(+), 32 deletions(-)
diff --git a/kernel/trace/Kconfig b/kernel/trace/Kconfig
index 084f34dc6c9f..0ab5916575a9 100644
--- a/kernel/trace/Kconfig
+++ b/kernel/trace/Kconfig
@@ -779,6 +779,18 @@ config PROBE_EVENTS_BTF_ARGS
kernel function entry or a tracepoint.
This is available only if BTF (BPF Type Format) support is enabled.
+config PROBE_EVENTS_DUMP_FETCHARG
+ bool "Dump of dynamic probe event fetch-arguments"
+ depends on PROBE_EVENTS
+ default n
+ help
+ This shows the dump of fetch-arguments of dynamic probe events
+ alongside their event definitions in the dynamic_events file
+ as comment lines. This is useful to debug the probe events.
+ Since this exposes the raw values in the dynamic_events file,
+ it might be a security risk. Only enable it if you need to debug
+ probe events themselves.
+
config KPROBE_EVENTS
depends on KPROBES
depends on HAVE_REGS_AND_STACK_ACCESS_API
diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c
index 50518b071414..462c31145733 100644
--- a/kernel/trace/trace_eprobe.c
+++ b/kernel/trace/trace_eprobe.c
@@ -87,6 +87,8 @@ static int eprobe_dyn_event_show(struct seq_file *m, struct dyn_event *ev)
seq_printf(m, " %s=%s", ep->tp.args[i].name, ep->tp.args[i].comm);
seq_putc(m, '\n');
+ trace_probe_dump_args(m, &ep->tp);
+
return 0;
}
diff --git a/kernel/trace/trace_fprobe.c b/kernel/trace/trace_fprobe.c
index 4d1abbf66229..536781cd4c47 100644
--- a/kernel/trace/trace_fprobe.c
+++ b/kernel/trace/trace_fprobe.c
@@ -1449,6 +1449,8 @@ static int trace_fprobe_show(struct seq_file *m, struct dyn_event *ev)
seq_printf(m, " %s=%s", tf->tp.args[i].name, tf->tp.args[i].comm);
seq_putc(m, '\n');
+ trace_probe_dump_args(m, &tf->tp);
+
return 0;
}
diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c
index a8420e6abb56..cfa807d8e760 100644
--- a/kernel/trace/trace_kprobe.c
+++ b/kernel/trace/trace_kprobe.c
@@ -1320,6 +1320,8 @@ static int trace_kprobe_show(struct seq_file *m, struct dyn_event *ev)
seq_printf(m, " %s=%s", tk->tp.args[i].name, tk->tp.args[i].comm);
seq_putc(m, '\n');
+ trace_probe_dump_args(m, &tk->tp);
+
return 0;
}
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 2ce7d62471cb..0908019aea12 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -2403,3 +2403,99 @@ int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_a
}
return 0;
}
+
+#ifdef CONFIG_PROBE_EVENTS_DUMP_FETCHARG
+
+struct fetch_op_decode {
+ const char *name;
+ void (*decode)(struct seq_file *m, struct fetch_insn *insn);
+};
+
+static const struct fetch_op_decode fetch_op_decode[];
+
+static void fetcharg_decode_none(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_puts(m, fetch_op_decode[insn->op].name);
+}
+
+static void fetcharg_decode_param(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(%u)", fetch_op_decode[insn->op].name, insn->param);
+}
+
+static void fetcharg_decode_imm(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(0x%lx)", fetch_op_decode[insn->op].name, insn->immediate);
+}
+
+static void fetcharg_decode_string(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(%s)", fetch_op_decode[insn->op].name, (char *)insn->data);
+}
+
+static void fetcharg_decode_symbol(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(%s)", fetch_op_decode[insn->op].name, (char *)insn->data);
+}
+
+static void fetcharg_decode_offset(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(offset=%d)", fetch_op_decode[insn->op].name, insn->offset);
+}
+
+static void fetcharg_decode_store(struct seq_file *m, struct fetch_insn *insn)
+{
+ if (insn->op == FETCH_OP_ST_RAW)
+ seq_printf(m, "%s(size=%u)", fetch_op_decode[insn->op].name, insn->size);
+ else
+ seq_printf(m, "%s(offset=%d,size=%u)", fetch_op_decode[insn->op].name,
+ insn->offset, insn->size);
+}
+
+static void fetcharg_decode_bf(struct seq_file *m, struct fetch_insn *insn)
+{
+ seq_printf(m, "%s(basesize=%u,lshift=%u,rshift=%u)",
+ fetch_op_decode[insn->op].name, insn->basesize, insn->lshift, insn->rshift);
+}
+
+static void fetcharg_decode_tp_arg(struct seq_file *m, struct fetch_insn *insn)
+{
+ struct ftrace_event_field *field = insn->data;
+
+ seq_printf(m, "%s(%s)", fetch_op_decode[insn->op].name, field->name);
+}
+
+#define FETCH_OP(opname, decode_fn) \
+ [FETCH_OP_##opname] = { .name = #opname, .decode = fetcharg_decode_##decode_fn }
+
+static const struct fetch_op_decode fetch_op_decode[] = FETCH_OP_LIST;
+#undef FETCH_OP
+
+static void trace_probe_dump_arg(struct seq_file *m, struct probe_arg *parg)
+{
+ int i;
+
+ seq_printf(m, "# %s: ", parg->name);
+ for (i = 0; i < FETCH_INSN_MAX; i++) {
+ struct fetch_insn *insn = parg->code + i;
+
+ if (insn->op >= ARRAY_SIZE(fetch_op_decode) || !fetch_op_decode[insn->op].decode)
+ seq_printf(m, "unknown(%d)", insn->op);
+ else
+ fetch_op_decode[insn->op].decode(m, insn);
+
+ if (insn->op == FETCH_OP_END)
+ break;
+ seq_puts(m, " -> ");
+ }
+ seq_putc(m, '\n');
+}
+
+void trace_probe_dump_args(struct seq_file *m, struct trace_probe *tp)
+{
+ int i;
+
+ for (i = 0; i < tp->nr_args; i++)
+ trace_probe_dump_arg(m, &tp->args[i]);
+}
+#endif /* CONFIG_PROBE_EVENTS_DUMP_FETCHARG */
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 2e0d8384ee5c..e36cfe39e9a8 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -83,38 +83,46 @@ static nokprobe_inline u32 update_data_loc(u32 loc, int consumed)
/* Printing function type */
typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
-enum fetch_op {
- FETCH_OP_NOP = 0,
- // Stage 1 (load) ops
- FETCH_OP_REG, /* Register : .param = offset */
- FETCH_OP_STACK, /* Stack : .param = index */
- FETCH_OP_STACKP, /* Stack pointer */
- FETCH_OP_RETVAL, /* Return value */
- FETCH_OP_IMM, /* Immediate : .immediate */
- FETCH_OP_COMM, /* Current comm */
- FETCH_OP_ARG, /* Function argument : .param */
- FETCH_OP_FOFFS, /* File offset: .immediate */
- FETCH_OP_IMMSTR, /* Allocated string: .data */
- FETCH_OP_EDATA, /* Entry data: .offset */
- // Stage 2 (dereference) op
- FETCH_OP_DEREF, /* Dereference: .offset */
- FETCH_OP_UDEREF, /* User-space Dereference: .offset */
- // Stage 3 (store) ops
- FETCH_OP_ST_RAW, /* Raw: .size */
- FETCH_OP_ST_MEM, /* Mem: .offset, .size */
- FETCH_OP_ST_UMEM, /* Mem: .offset, .size */
- FETCH_OP_ST_STRING, /* String: .offset, .size */
- FETCH_OP_ST_USTRING, /* User String: .offset, .size */
- FETCH_OP_ST_SYMSTR, /* Kernel Symbol String: .offset, .size */
- FETCH_OP_ST_EDATA, /* Store Entry Data: .offset */
- // Stage 4 (modify) op
- FETCH_OP_MOD_BF, /* Bitfield: .basesize, .lshift, .rshift */
- // Stage 5 (loop) op
- FETCH_OP_LP_ARRAY, /* Array: .param = loop count */
- FETCH_OP_TP_ARG, /* Trace Point argument */
- FETCH_OP_END,
- FETCH_NOP_SYMBOL, /* Unresolved Symbol holder */
-};
+#define FETCH_OP_LIST { \
+ /* Stage 1 (load) ops */ \
+ FETCH_OP(NOP, none), /* NOP */ \
+ FETCH_OP(REG, param), /* Register: .param = offset */ \
+ FETCH_OP(STACK, param), /* Stack: .param = index */ \
+ FETCH_OP(STACKP, none), /* Stack pointer */ \
+ FETCH_OP(RETVAL, none), /* Return value */ \
+ FETCH_OP(IMM, imm), /* Immediate: .immediate */ \
+ FETCH_OP(COMM, none), /* Current comm */ \
+ FETCH_OP(ARG, param), /* Argument: .param = index */ \
+ FETCH_OP(FOFFS, imm), /* File offset: .immediate */ \
+ FETCH_OP(IMMSTR, string), /* Allocated string: .data */ \
+ FETCH_OP(EDATA, offset), /* Entry data: .offset */ \
+ FETCH_OP(TP_ARG, tp_arg), /* Tracepoint argument: .data */\
+ /* Stage 2 (dereference) ops */ \
+ FETCH_OP(DEREF, offset), /* Dereference: .offset */ \
+ FETCH_OP(UDEREF, offset), /* User-space dereference: .offset */\
+ /* Stage 3 (store) ops */ \
+ FETCH_OP(ST_RAW, store), /* Raw value: .size */ \
+ FETCH_OP(ST_MEM, store), /* Memory: .offset, .size */ \
+ FETCH_OP(ST_UMEM, store), /* User memory: .offset, .size */\
+ FETCH_OP(ST_STRING, store), /* String: .offset, .size */ \
+ FETCH_OP(ST_USTRING, store), /* User string: .offset, .size */\
+ FETCH_OP(ST_SYMSTR, store), /* Symbol name: .offset, .size */\
+ FETCH_OP(ST_EDATA, offset), /* Entry data: .offset */ \
+ /* Stage 4 (modify) op */ \
+ FETCH_OP(MOD_BF, bf), /* Bitfield: .basesize, .lshift, .rshift*/\
+ /* Stage 5 (loop) op */ \
+ FETCH_OP(LP_ARRAY, param), /* Loop array: .param = count */\
+ /* End */ \
+ FETCH_OP(END, none), \
+ /* Unresolved Symbol holder */ \
+ FETCH_OP(NOP_SYMBOL, symbol), /* Non loaded symbol: .data = symbol name */\
+}
+
+#define FETCH_OP(opname, decode_fn) FETCH_OP_##opname
+enum fetch_op FETCH_OP_LIST;
+#undef FETCH_OP
+
+#define FETCH_NOP_SYMBOL FETCH_OP_NOP_SYMBOL
struct fetch_insn {
enum fetch_op op;
@@ -370,6 +378,13 @@ bool trace_probe_match_command_args(struct trace_probe *tp,
int trace_probe_create(const char *raw_command, int (*createfn)(int, const char **));
int trace_probe_print_args(struct trace_seq *s, struct probe_arg *args, int nr_args,
u8 *data, void *field);
+#ifdef CONFIG_PROBE_EVENTS_DUMP_FETCHARG
+void trace_probe_dump_args(struct seq_file *m, struct trace_probe *tp);
+#else
+static inline void trace_probe_dump_args(struct seq_file *m, struct trace_probe *tp)
+{
+}
+#endif
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
int traceprobe_get_entry_data_size(struct trace_probe *tp);
diff --git a/kernel/trace/trace_uprobe.c b/kernel/trace/trace_uprobe.c
index c274346853d1..b2e264a4b96c 100644
--- a/kernel/trace/trace_uprobe.c
+++ b/kernel/trace/trace_uprobe.c
@@ -765,6 +765,9 @@ static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev)
seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm);
seq_putc(m, '\n');
+
+ trace_probe_dump_args(m, &tu->tp);
+
return 0;
}
^ permalink raw reply related
* [PATCH v13 03/11] tools/bootconfig: Ignore comment lines in dynamic_events/kprobe_events file
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since dynamic_events/kprobe_events files show the fetcharg debug
information as comment lines, its reader needs to ignore it.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
tools/bootconfig/scripts/ftrace2bconf.sh | 2 ++
1 file changed, 2 insertions(+)
diff --git a/tools/bootconfig/scripts/ftrace2bconf.sh b/tools/bootconfig/scripts/ftrace2bconf.sh
index 1603801cf126..8eed445c295e 100755
--- a/tools/bootconfig/scripts/ftrace2bconf.sh
+++ b/tools/bootconfig/scripts/ftrace2bconf.sh
@@ -57,6 +57,8 @@ EOF
kprobe_event_options() {
cat $TRACEFS/kprobe_events | while read p args; do
case $p in
+ \#*)
+ continue;;
r*)
cat 1>&2 << EOF
# WARN: A return probe found but it is not supported by bootconfig. Skip it.
^ permalink raw reply related
* [PATCH v13 04/11] perf/probe: Ignore comment lines in dynamic_events/kprobe_events file
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since dynamic_events/kprobe_events files show the fetcharg debug
information as comment lines, its reader needs to ignore it.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
tools/perf/util/probe-file.c | 2 ++
1 file changed, 2 insertions(+)
diff --git a/tools/perf/util/probe-file.c b/tools/perf/util/probe-file.c
index 4032572cbf55..4d12693a83b3 100644
--- a/tools/perf/util/probe-file.c
+++ b/tools/perf/util/probe-file.c
@@ -197,6 +197,8 @@ struct strlist *probe_file__get_rawlist(int fd)
idx = strlen(p) - 1;
if (p[idx] == '\n')
p[idx] = '\0';
+ if (buf[0] == '#')
+ continue;
ret = strlist__add(sl, buf);
if (ret < 0) {
pr_debug("strlist__add failed (%d)\n", ret);
^ permalink raw reply related
* [PATCH v13 05/11] tracing/probes: Support typecast for various probe events
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Support BTF typecast feature on other probe events, but only if it is
kernel function entry or return, and must use function parameter name
or $retval. This means you can do:
(STRUCT)PARAM->MEMBER
Note: you can not use other variables like $stackN, %reg etc. That
needs nesting support.
To support other probe events, we just need to use last_struct type
when we find a function parameter in parse_btf_arg().
This also updates <tracefs>/README file to show struct typecast.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v5:
- Add comments about $retval with typecast.
- Even if the type of retvalue is not known, if user specifies typecast,
use it for its type.
Changes in v3:
- Clarify the limitation.
Changes in v2:
- Fix to re-enable typecast on eprobe.
---
Documentation/trace/fprobetrace.rst | 3 +++
Documentation/trace/kprobetrace.rst | 4 ++++
kernel/trace/trace.c | 2 +-
kernel/trace/trace_probe.c | 23 +++++++++++++++++------
kernel/trace/trace_probe.h | 5 +++++
5 files changed, 30 insertions(+), 7 deletions(-)
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index b4c2ca3d02c1..7435ded2d66d 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -57,6 +57,9 @@ Synopsis of fprobe-events
(u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal types
(x8/x16/x32/x64), "char", "string", "ustring", "symbol", "symstr"
and bitfield are supported.
+ (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ a pointer to STRUCT and then derference the pointer defined by
+ ->MEMBER.
(\*1) This is available only when BTF is enabled.
(\*2) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index 3b6791c17e9b..f73614997d52 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -61,6 +61,10 @@ Synopsis of kprobe_events
(x8/x16/x32/x64), VFS layer common type(%pd/%pD), "char",
"string", "ustring", "symbol", "symstr" and bitfield are
supported.
+ (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ a pointer to STRUCT and then derference the pointer defined by
+ ->MEMBER. Note that this is available only when the probe is
+ on function entry.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
is best effort, because depending on the argument type, it may be passed on
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 1146b83b711a..280a3dccd13f 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4322,7 +4322,7 @@ static const char readme_msg[] =
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
- "\t <argname>[->field[->field|.field...]],\n"
+ "\t [(structname)]<argname>[->field[->field|.field...]],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 0908019aea12..e6cc9f3d6c8b 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -699,7 +699,7 @@ static int parse_btf_arg(char *varname,
if (ctx->flags & TPARG_FL_RETURN && !strcmp(varname, "$retval")) {
code->op = FETCH_OP_RETVAL;
- /* Check whether the function return type is not void */
+ /* Check whether the function return type is not void, even with typecast. */
if (query_btf_context(ctx) == 0) {
if (ctx->proto->type == 0) {
trace_probe_log_err(ctx->offset, NO_RETVAL);
@@ -708,6 +708,13 @@ static int parse_btf_arg(char *varname,
tid = ctx->proto->type;
goto found;
}
+ /*
+ * Even if we can not find appropriate BTF info, we can still access
+ * the field via typecast.
+ */
+ if (ctx->struct_btf)
+ goto found;
+
if (field) {
trace_probe_log_err(ctx->offset + field - varname,
NO_BTF_ENTRY);
@@ -752,7 +759,10 @@ static int parse_btf_arg(char *varname,
return -ENOENT;
found:
- type = btf_type_skip_modifiers(ctx->btf, tid, NULL);
+ if (ctx->struct_btf)
+ type = ctx->last_struct;
+ else
+ type = btf_type_skip_modifiers(ctx->btf, tid, NULL);
found_type:
if (!type) {
trace_probe_log_err(ctx->offset, BAD_BTF_TID);
@@ -829,10 +839,11 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
char *tmp;
int ret;
- /* Currently this only works for eprobes */
- if (!(ctx->flags & TPARG_FL_TEVENT)) {
- trace_probe_log_err(ctx->offset, TYPECAST_NOT_EVENT);
- return -EINVAL;
+ if (!(tparg_is_event_probe(ctx->flags) ||
+ tparg_is_function_entry(ctx->flags) ||
+ tparg_is_function_return(ctx->flags))) {
+ trace_probe_log_err(ctx->offset, NOSUP_BTFARG);
+ return -EOPNOTSUPP;
}
tmp = strchr(arg, ')');
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index e36cfe39e9a8..aa72e2ffdd93 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -429,6 +429,11 @@ static inline bool tparg_is_function_return(unsigned int flags)
return (flags & TPARG_FL_LOC_MASK) == (TPARG_FL_KERNEL | TPARG_FL_RETURN);
}
+static inline bool tparg_is_event_probe(unsigned int flags)
+{
+ return !!(flags & TPARG_FL_TEVENT);
+}
+
struct traceprobe_parse_context {
struct trace_event_call *event;
/* BTF related parameters */
^ permalink raw reply related
* [PATCH v13 06/11] tracing/probes: Support nested typecast
From: Masami Hiramatsu (Google) @ 2026-06-29 6:13 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When we hit an open parenthesis right after typecast closing
parenthesis, it means we have nested typecast. This allows us to
typecast a generic data member in a structure to a pointer to
another structure.
For example, to cast a DATA_MEMBER of VAR structure to STRUCT pointer
and get MEMBER value.
(STRUCT)(VAR->DATA_MEMBER)->MEMBER
Also, we can nest typecast.
(STRUCT1)((STRUCT2)$ARG->FIELD2)->FIELD1
Currently the max nest level is limited to 3.
This also allows user to use typecasting for registers or stacks on
kprobe events. e.g.
(STRUCT)(%ax)->MEMBER
(STRUCT)($stack0)->MEMBER
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v11:
- Fix to return -EINVAL if WARN_ON_ONCE() is hit.
Changes in v6:
- Add a WARN_ON_ONCE check for leaking nested_level (it must not happen.)
Changes in v4:
- Use orig_offset for reporting NO_PTR_STRCT error.
Changes in v2:
- Fix to skip "->" after closing parenthetsis.
---
Documentation/trace/eprobetrace.rst | 2 +
Documentation/trace/fprobetrace.rst | 2 +
Documentation/trace/kprobetrace.rst | 2 +
kernel/trace/trace.c | 1
kernel/trace/trace_probe.c | 83 ++++++++++++++++++++++++++++++++---
kernel/trace/trace_probe.h | 7 +++
6 files changed, 88 insertions(+), 9 deletions(-)
diff --git a/Documentation/trace/eprobetrace.rst b/Documentation/trace/eprobetrace.rst
index fe3602540569..cd0b4aa7f896 100644
--- a/Documentation/trace/eprobetrace.rst
+++ b/Documentation/trace/eprobetrace.rst
@@ -50,6 +50,8 @@ Synopsis of eprobe_events
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that when this is used, the FIELD name does not
need to be prefixed with a '$'.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
Types
-----
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 7435ded2d66d..6b8bb27bb62d 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -60,6 +60,8 @@ Synopsis of fprobe-events
(STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
(\*1) This is available only when BTF is enabled.
(\*2) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index f73614997d52..c4382765d5b2 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -65,6 +65,8 @@ Synopsis of kprobe_events
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that this is available only when the probe is
on function entry.
+ (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ also be used with another FETCHARG instead of FIELD.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
is best effort, because depending on the argument type, it may be passed on
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 280a3dccd13f..e56ee034c486 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4323,6 +4323,7 @@ static const char readme_msg[] =
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
"\t [(structname)]<argname>[->field[->field|.field...]],\n"
+ "\t [(structname)](fetcharg)->field[->field|.field...],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index e6cc9f3d6c8b..827ae04f6351 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -832,10 +832,35 @@ static int query_btf_struct(const char *sname, struct traceprobe_parse_context *
return 0;
}
+/* Find the matching closing parenthesis for a given opening parenthesis. */
+static char *find_matched_close_paren(char *s)
+{
+ char *p = s;
+ int count = 0;
+
+ while (*p) {
+ if (*p == '(')
+ count++;
+ else if (*p == ')') {
+ if (--count == 0)
+ return p;
+ }
+ p++;
+ }
+ return NULL;
+}
+
+static int
+parse_probe_arg(char *arg, const struct fetch_type *type,
+ struct fetch_insn **pcode, struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx);
+
static int handle_typecast(char *arg, struct fetch_insn **pcode,
struct fetch_insn *end,
struct traceprobe_parse_context *ctx)
{
+ int orig_offset = ctx->offset;
+ bool nested = false;
char *tmp;
int ret;
@@ -852,19 +877,56 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
DEREF_OPEN_BRACE);
return -EINVAL;
}
- *tmp = '\0';
- ret = query_btf_struct(arg + 1, ctx);
- *tmp = ')';
+ *tmp++ = '\0';
+ /* Handle the nested structure like (STRUCT)(VAR->FIELD)->... */
+ if (*tmp == '(') {
+ char *close = find_matched_close_paren(tmp);
+
+ ctx->offset += tmp - arg;
+ if (!close) {
+ trace_probe_log_err(ctx->offset, DEREF_OPEN_BRACE);
+ return -EINVAL;
+ }
+ /* We expect a field access for typecast */
+ if (close[1] != '-' || close[2] != '>') {
+ trace_probe_log_err(ctx->offset + close - tmp + 1,
+ TYPECAST_REQ_FIELD);
+ return -EINVAL;
+ }
+
+ ctx->nested_level++;
+ if (ctx->nested_level > TRACEPROBE_MAX_NESTED_LEVEL) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_NESTED);
+ return -E2BIG;
+ }
+ *close = '\0';
+
+ ctx->offset += 1; /* for the '(' */
+ /* We need to parse the nested one */
+ ret = parse_probe_arg(tmp + 1, find_fetch_type(NULL, ctx->flags),
+ pcode, end, ctx);
+ if (ret < 0)
+ return ret;
+ ctx->nested_level--;
+ clear_struct_btf(ctx);
+
+ tmp = close + 3;/* Skip "->" after closing parenthesis */
+ nested = true;
+ }
+
+ ret = query_btf_struct(arg + 1, ctx);
if (ret < 0) {
- trace_probe_log_err(ctx->offset + 1, NO_PTR_STRCT);
+ trace_probe_log_err(orig_offset + 1, NO_PTR_STRCT);
return -EINVAL;
}
- tmp++;
-
- ctx->offset += tmp - arg;
- ret = parse_btf_arg(tmp, pcode, end, ctx);
+ ctx->offset = orig_offset + tmp - arg;
+ /* If it is nested, tmp points to the field name. */
+ if (nested)
+ ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
+ else
+ ret = parse_btf_arg(tmp, pcode, end, ctx);
return ret;
}
@@ -1638,6 +1700,11 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size,
ctx);
if (ret < 0)
goto fail;
+ /* nested_level must be 0 here, otherwise there is a bug. */
+ if (WARN_ON_ONCE(ctx->nested_level)) {
+ ret = -EINVAL;
+ goto fail;
+ }
/* Update storing type if BTF is available */
if (IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS) &&
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index aa72e2ffdd93..7d71925244e8 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -450,8 +450,11 @@ struct traceprobe_parse_context {
struct trace_probe *tp;
unsigned int flags;
int offset;
+ int nested_level;
};
+#define TRACEPROBE_MAX_NESTED_LEVEL 3
+
extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
const char *argv,
struct traceprobe_parse_context *ctx);
@@ -587,7 +590,9 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(TOO_MANY_ARGS, "Too many arguments are specified"), \
C(TOO_MANY_EARGS, "Too many entry arguments specified"), \
C(EVENT_TOO_BIG, "Event too big (too many fields?)"), \
- C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"),
+ C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"), \
+ C(TYPECAST_REQ_FIELD, "Typecast requires a field access"), \
+ C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"),
#undef C
#define C(a, b) TP_ERR_##a
^ permalink raw reply related
* [PATCH v13 07/11] tracing/probes: Type casting always involves nested calls
From: Masami Hiramatsu (Google) @ 2026-06-29 6:14 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
This allows type casting to various fetchargs without parentheses
by recursively calling parse_probe_arg on the target when type
casting is used.
For example, this allows the following expressions:
- (STRUCT)%REG->FIELD
- (STRUCT)$stackN->FIELD
- (STRUCT)@SYM->FIELD
Note that @SYM+/-OFFSET with typecast needs parentheses like:
- (STRUCT)(@SYM-8)->FIELD
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v8:
- Fix caret position in error case.
- Add a comment about @SYM+/-OFFSET without parentheses.
Changes in v7:
- Prohibit using @SYM+/-OFFSET without parentheses.
- Cleanup parse_btf_arg() since ctx->struct_btf is always NULL now.
Changes in v6:
- Newly added.
---
kernel/trace/trace_probe.c | 123 ++++++++++++++++++++++++++------------------
kernel/trace/trace_probe.h | 4 +
2 files changed, 75 insertions(+), 52 deletions(-)
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 827ae04f6351..1b97b125e9cb 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -684,19 +684,6 @@ static int parse_btf_arg(char *varname,
return -EOPNOTSUPP;
}
- if (ctx->flags & TPARG_FL_TEVENT) {
- ret = parse_trace_event(varname, code, ctx);
- if (ret < 0) {
- trace_probe_log_err(ctx->offset, BAD_ATTACH_ARG);
- return ret;
- }
- /* TEVENT is only here via a typecast */
- if (WARN_ON_ONCE(ctx->struct_btf == NULL))
- return -EINVAL;
- type = ctx->last_struct;
- goto found_type;
- }
-
if (ctx->flags & TPARG_FL_RETURN && !strcmp(varname, "$retval")) {
code->op = FETCH_OP_RETVAL;
/* Check whether the function return type is not void, even with typecast. */
@@ -708,13 +695,6 @@ static int parse_btf_arg(char *varname,
tid = ctx->proto->type;
goto found;
}
- /*
- * Even if we can not find appropriate BTF info, we can still access
- * the field via typecast.
- */
- if (ctx->struct_btf)
- goto found;
-
if (field) {
trace_probe_log_err(ctx->offset + field - varname,
NO_BTF_ENTRY);
@@ -759,11 +739,7 @@ static int parse_btf_arg(char *varname,
return -ENOENT;
found:
- if (ctx->struct_btf)
- type = ctx->last_struct;
- else
- type = btf_type_skip_modifiers(ctx->btf, tid, NULL);
-found_type:
+ type = btf_type_skip_modifiers(ctx->btf, tid, NULL);
if (!type) {
trace_probe_log_err(ctx->offset, BAD_BTF_TID);
return -EINVAL;
@@ -860,7 +836,7 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
struct traceprobe_parse_context *ctx)
{
int orig_offset = ctx->offset;
- bool nested = false;
+ char *close;
char *tmp;
int ret;
@@ -871,6 +847,17 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
return -EOPNOTSUPP;
}
+ /*
+ * Always consider the token after typecast as a nested call
+ * For example: (STRUCT)VAR->FIELD and (STRUCT)(VAR)->FIELD are same.
+ * VAR is solved in the nested call.
+ */
+ ctx->nested_level++;
+ if (ctx->nested_level > TRACEPROBE_MAX_NESTED_LEVEL) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_NESTED);
+ return -E2BIG;
+ }
+
tmp = strchr(arg, ')');
if (!tmp) {
trace_probe_log_err(ctx->offset + strlen(arg),
@@ -879,11 +866,10 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
}
*tmp++ = '\0';
- /* Handle the nested structure like (STRUCT)(VAR->FIELD)->... */
+ ctx->offset += tmp - arg;
if (*tmp == '(') {
- char *close = find_matched_close_paren(tmp);
+ close = find_matched_close_paren(tmp);
- ctx->offset += tmp - arg;
if (!close) {
trace_probe_log_err(ctx->offset, DEREF_OPEN_BRACE);
return -EINVAL;
@@ -894,27 +880,66 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
TYPECAST_REQ_FIELD);
return -EINVAL;
}
-
- ctx->nested_level++;
- if (ctx->nested_level > TRACEPROBE_MAX_NESTED_LEVEL) {
- trace_probe_log_err(ctx->offset, TOO_MANY_NESTED);
- return -E2BIG;
+ /* Skip '(' */
+ ctx->offset += 1;
+ tmp++;
+ } else if (*tmp == '+' || *tmp == '-') {
+ /* Dereference can have another field access inside it. */
+ char *open = strchr(tmp + 1, '(');
+
+ if (!open) {
+ trace_probe_log_err(ctx->offset,
+ DEREF_NEED_BRACE);
+ return -EINVAL;
+ }
+ close = find_matched_close_paren(open);
+ if (!close) {
+ trace_probe_log_err(ctx->offset + strlen(tmp),
+ DEREF_OPEN_BRACE);
+ return -EINVAL;
+ }
+ close++;
+ /* We expect a field access for typecast */
+ if (close[0] != '-' || close[1] != '>') {
+ trace_probe_log_err(ctx->offset + close - tmp,
+ TYPECAST_REQ_FIELD);
+ return -EINVAL;
+ }
+ } else {
+ if (tmp[0] == '@') {
+ /* @sym+offset is not allowed without parenthesized */
+ close = strpbrk(tmp, "+-");
+ if (close && isdigit(close[1])) {
+ trace_probe_log_err(ctx->offset,
+ TYPECAST_SYM_OFFSET);
+ return -EINVAL;
+ }
}
- *close = '\0';
+ /* Inner variable name */
+ close = strchr(tmp, '-');
+ if (!close || close[1] != '>') {
+ trace_probe_log_err(ctx->offset + strlen(tmp),
+ TYPECAST_REQ_FIELD);
+ return -EINVAL;
+ }
+ }
+ *close = '\0';
- ctx->offset += 1; /* for the '(' */
- /* We need to parse the nested one */
- ret = parse_probe_arg(tmp + 1, find_fetch_type(NULL, ctx->flags),
- pcode, end, ctx);
- if (ret < 0)
- return ret;
- ctx->nested_level--;
- clear_struct_btf(ctx);
+ /* We need to parse the nested one */
+ ret = parse_probe_arg(tmp, find_fetch_type(NULL, ctx->flags),
+ pcode, end, ctx);
+ if (ret < 0)
+ return ret;
+ ctx->nested_level--;
+ clear_struct_btf(ctx);
- tmp = close + 3;/* Skip "->" after closing parenthesis */
- nested = true;
- }
+ /* Let tmp point the field name. */
+ if (close[1] == '-')
+ tmp = close + 3; /* Skip "->" after closing parenthesis */
+ else
+ tmp = close + 2; /* Skip ">" after inner variable name */
+ /* resolve the typecast struct name */
ret = query_btf_struct(arg + 1, ctx);
if (ret < 0) {
trace_probe_log_err(orig_offset + 1, NO_PTR_STRCT);
@@ -922,11 +947,7 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
}
ctx->offset = orig_offset + tmp - arg;
- /* If it is nested, tmp points to the field name. */
- if (nested)
- ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
- else
- ret = parse_btf_arg(tmp, pcode, end, ctx);
+ ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
return ret;
}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 7d71925244e8..f4fbe3010978 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -453,6 +453,7 @@ struct traceprobe_parse_context {
int nested_level;
};
+/* Each typecast consumes nested level. So the max number of typecast is 3. */
#define TRACEPROBE_MAX_NESTED_LEVEL 3
extern int traceprobe_parse_probe_arg(struct trace_probe *tp, int i,
@@ -592,7 +593,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(EVENT_TOO_BIG, "Event too big (too many fields?)"), \
C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"), \
C(TYPECAST_REQ_FIELD, "Typecast requires a field access"), \
- C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"),
+ C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"), \
+ C(TYPECAST_SYM_OFFSET, "@SYM+/-OFFSET with typecast needs parentheses")
#undef C
#define C(a, b) TP_ERR_##a
^ permalink raw reply related
* [PATCH v13 08/11] tracing/probes: Support field specifier option for typecast
From: Masami Hiramatsu (Google) @ 2026-06-29 6:14 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Add a field specifier option for the typecast. This works like
container_of() macro.
(STRUCT[,FIELD[.FIELD2...]])VAR
This is equivalent to :
container_of(VAR, struct STRUCT, FIELD[.FIELD2...])
For example:
echo "f tick_nohz_handler next_tick=(tick_sched,sched_timer)timer->next_tick" >> dynamic_events
This will trace tick_nohz_handler() with its tick_sched::next_tick which
is converted from @timer by contianer_of(tick, struct tick_sched, sched_timer).
So, if you enabkle both fprobes:tick_nohz_handler__entry and
timer:hrtimer_expire_entry events, we will see something like:
<idle>-0 [002] d.h1. 3778.087272: hrtimer_expire_entry: hrtimer=00000000d63db328 f
unction=tick_nohz_handler now=3777450051040
<idle>-0 [002] d.h1. 3778.087281: tick_nohz_handler__entry: (tick_nohz_handler+0x4
/0x140) next_tick=3777450000000
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v13:
- Fix missed comma after TYPECAST_SYM_OFFSET error.
Changes in v6:
- Update according to the allways nested patch.
Changes in v3:
- Fix error caret position.
Changes in v2:
- Use byteoffset for typecast field offset instead of bitoffset. This fixes negative modulo calculation.
- Check whether a field is specified after typecast.
- Reject if typecast field option has arrow operator.
---
Documentation/trace/eprobetrace.rst | 5 +
Documentation/trace/fprobetrace.rst | 8 +-
Documentation/trace/kprobetrace.rst | 8 +-
kernel/trace/trace.c | 4 -
kernel/trace/trace_probe.c | 169 ++++++++++++++++++++++++-----------
kernel/trace/trace_probe.h | 5 +
6 files changed, 135 insertions(+), 64 deletions(-)
diff --git a/Documentation/trace/eprobetrace.rst b/Documentation/trace/eprobetrace.rst
index cd0b4aa7f896..680e0af43d5d 100644
--- a/Documentation/trace/eprobetrace.rst
+++ b/Documentation/trace/eprobetrace.rst
@@ -49,7 +49,10 @@ Synopsis of eprobe_events
(STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that when this is used, the FIELD name does not
- need to be prefixed with a '$'.
+ need to be prefixed with a '$'. ASGN can be specified optionally.
+ If ASGN is specified, FIELD will be cast to the same offset
+ position as the ASGN member, rather than to the beginning of
+ the STRUCT.
(STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 6b8bb27bb62d..290a9e6f7491 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -57,10 +57,12 @@ Synopsis of fprobe-events
(u8/u16/u32/u64/s8/s16/s32/s64), hexadecimal types
(x8/x16/x32/x64), "char", "string", "ustring", "symbol", "symstr"
and bitfield are supported.
- (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ (STRUCT[,ASGN])FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
- ->MEMBER.
- (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ ->MEMBER. ASGN can be specified optionally. If ASGN is specified,
+ FIELD will be cast to the same offset position as the ASGN member,
+ rather than to the beginning of the STRUCT.
+ (STRUCT[,ASGN])(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
(\*1) This is available only when BTF is enabled.
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index c4382765d5b2..a62707e6a9f2 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -61,11 +61,13 @@ Synopsis of kprobe_events
(x8/x16/x32/x64), VFS layer common type(%pd/%pD), "char",
"string", "ustring", "symbol", "symstr" and bitfield are
supported.
- (STRUCT)FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
+ (STRUCT[,ASGN])FIELD->MEMBER[->MEMBER] : If BTF is supported, typecast FIELD to
a pointer to STRUCT and then derference the pointer defined by
->MEMBER. Note that this is available only when the probe is
- on function entry.
- (STRUCT)(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
+ on function entry. ASGN can be specified optionally. If ASGN
+ is specified, FIELD will be cast to the same offset position
+ as the ASGN member, rather than to the beginning of the STRUCT.
+ (STRUCT[,ASGN])(FETCHARG)->MEMBER[->MEMBER] : typecast can nest, so the above can
also be used with another FETCHARG instead of FIELD.
(\*1) only for the probe on function entry (offs == 0). Note, this argument access
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index e56ee034c486..5670c4b91dc0 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4322,8 +4322,8 @@ static const char readme_msg[] =
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
"\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
- "\t [(structname)]<argname>[->field[->field|.field...]],\n"
- "\t [(structname)](fetcharg)->field[->field|.field...],\n"
+ "\t [(structname[,field])]<argname>[->field[->field|.field...]],\n"
+ "\t [(structname[,field])](fetcharg)->field[->field|.field...],\n"
#endif
#else
"\t $stack<index>, $stack, $retval, $comm,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 1b97b125e9cb..fd006b415c68 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -568,6 +568,64 @@ static int split_next_field(char *varname, char **next_field,
return ret;
}
+/* Inner loop for solving dot operator ('.'). Return bit-offset of the given field */
+static int get_bitoffset_of_field(char **pfieldname, const struct btf_type **ptype,
+ struct traceprobe_parse_context *ctx)
+{
+ const struct btf_type *type = *ptype;
+ const struct btf_member *field;
+ struct btf *btf = ctx_btf(ctx);
+ char *fieldname = *pfieldname;
+ int bitoffs = 0;
+ u32 anon_offs;
+ char *next;
+ int is_ptr;
+
+ do {
+ next = NULL;
+ is_ptr = split_next_field(fieldname, &next, ctx);
+ if (is_ptr < 0)
+ return is_ptr;
+
+ anon_offs = 0;
+ field = btf_find_struct_member(btf, type, fieldname,
+ &anon_offs);
+ if (IS_ERR(field)) {
+ trace_probe_log_err(ctx->offset, BAD_BTF_TID);
+ return PTR_ERR(field);
+ }
+ if (!field) {
+ trace_probe_log_err(ctx->offset, NO_BTF_FIELD);
+ return -ENOENT;
+ }
+ /* Add anonymous structure/union offset */
+ bitoffs += anon_offs;
+
+ /* Accumulate the bit-offsets of the dot-connected fields */
+ if (btf_type_kflag(type)) {
+ bitoffs += BTF_MEMBER_BIT_OFFSET(field->offset);
+ ctx->last_bitsize = BTF_MEMBER_BITFIELD_SIZE(field->offset);
+ } else {
+ bitoffs += field->offset;
+ ctx->last_bitsize = 0;
+ }
+
+ type = btf_type_skip_modifiers(btf, field->type, NULL);
+ if (!type) {
+ trace_probe_log_err(ctx->offset, BAD_BTF_TID);
+ return -EINVAL;
+ }
+
+ if (next)
+ ctx->offset += next - fieldname;
+ fieldname = next;
+ } while (!is_ptr && fieldname);
+
+ *pfieldname = fieldname;
+ *ptype = type;
+
+ return bitoffs;
+}
/*
* Parse the field of data structure. The @type must be a pointer type
* pointing the target data structure type.
@@ -577,15 +635,13 @@ static int parse_btf_field(char *fieldname, const struct btf_type *type,
struct traceprobe_parse_context *ctx)
{
struct fetch_insn *code = *pcode;
- const struct btf_member *field;
- u32 bitoffs, anon_offs;
- bool is_struct = ctx->struct_btf != NULL;
struct btf *btf = ctx_btf(ctx);
- char *next;
- int is_ptr;
+ bool is_first_field = true;
+ int bitoffs;
do {
- if (!is_struct) {
+ /* For the first field of typecast, @type will be the target structure type. */
+ if (!(is_first_field && ctx->struct_btf)) {
/* Outer loop for solving arrow operator ('->') */
if (BTF_INFO_KIND(type->info) != BTF_KIND_PTR) {
trace_probe_log_err(ctx->offset, NO_PTR_STRCT);
@@ -599,60 +655,25 @@ static int parse_btf_field(char *fieldname, const struct btf_type *type,
return -EINVAL;
}
}
- /* Only the first type can skip being a pointer */
- is_struct = false;
-
- bitoffs = 0;
- do {
- /* Inner loop for solving dot operator ('.') */
- next = NULL;
- is_ptr = split_next_field(fieldname, &next, ctx);
- if (is_ptr < 0)
- return is_ptr;
-
- anon_offs = 0;
- field = btf_find_struct_member(btf, type, fieldname,
- &anon_offs);
- if (IS_ERR(field)) {
- trace_probe_log_err(ctx->offset, BAD_BTF_TID);
- return PTR_ERR(field);
- }
- if (!field) {
- trace_probe_log_err(ctx->offset, NO_BTF_FIELD);
- return -ENOENT;
- }
- /* Add anonymous structure/union offset */
- bitoffs += anon_offs;
-
- /* Accumulate the bit-offsets of the dot-connected fields */
- if (btf_type_kflag(type)) {
- bitoffs += BTF_MEMBER_BIT_OFFSET(field->offset);
- ctx->last_bitsize = BTF_MEMBER_BITFIELD_SIZE(field->offset);
- } else {
- bitoffs += field->offset;
- ctx->last_bitsize = 0;
- }
-
- type = btf_type_skip_modifiers(btf, field->type, NULL);
- if (!type) {
- trace_probe_log_err(ctx->offset, BAD_BTF_TID);
- return -EINVAL;
- }
-
- ctx->offset += next - fieldname;
- fieldname = next;
- } while (!is_ptr && fieldname);
+ bitoffs = get_bitoffset_of_field(&fieldname, &type, ctx);
+ if (bitoffs < 0)
+ return bitoffs;
if (++code == end) {
trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
return -EINVAL;
}
code->op = FETCH_OP_DEREF; /* TODO: user deref support */
code->offset = bitoffs / 8;
+ if (is_first_field && ctx->struct_btf) {
+ /* The first field can be typecasted with field option. */
+ code->offset -= ctx->prefix_byteoffs;
+ }
*pcode = code;
ctx->last_bitoffs = bitoffs % 8;
ctx->last_type = type;
+ is_first_field = false;
} while (fieldname);
return 0;
@@ -808,6 +829,46 @@ static int query_btf_struct(const char *sname, struct traceprobe_parse_context *
return 0;
}
+static int parse_btf_casttype(char *casttype, struct traceprobe_parse_context *ctx)
+{
+ char *field;
+ int ret;
+
+ /* Field option - evaluated later. */
+ field = strchr(casttype, ',');
+ if (field)
+ *field++ = '\0';
+
+ ret = query_btf_struct(casttype, ctx);
+ if (ret < 0) {
+ trace_probe_log_err(ctx->offset, NO_PTR_STRCT);
+ return -EINVAL;
+ }
+
+ if (field) {
+ struct btf_type *type = (struct btf_type *)ctx->last_struct;
+
+ ctx->offset += field - casttype;
+ ret = get_bitoffset_of_field(&field, &ctx->last_struct, ctx);
+ if (ret < 0)
+ return ret;
+ if (ret % 8) {
+ trace_probe_log_err(ctx->offset, TYPECAST_NOT_ALIGNED);
+ return -EINVAL;
+ }
+ if (field != NULL) {
+ /* this means @field skips an arrow operator ("->"). */
+ trace_probe_log_err(ctx->offset - 2, TYPECAST_BAD_ARROW);
+ return -EINVAL;
+ }
+ ctx->prefix_byteoffs = ret / 8;
+ /* Restore the original struct type (overwritten by get_bitoffset_of_field) */
+ ctx->last_struct = type;
+ }
+
+ return ret;
+}
+
/* Find the matching closing parenthesis for a given opening parenthesis. */
static char *find_matched_close_paren(char *s)
{
@@ -940,14 +1001,14 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
tmp = close + 2; /* Skip ">" after inner variable name */
/* resolve the typecast struct name */
- ret = query_btf_struct(arg + 1, ctx);
- if (ret < 0) {
- trace_probe_log_err(orig_offset + 1, NO_PTR_STRCT);
- return -EINVAL;
- }
+ ctx->offset = orig_offset + 1; /* for the '(' */
+ ret = parse_btf_casttype(arg + 1, ctx);
+ if (ret < 0)
+ return ret;
ctx->offset = orig_offset + tmp - arg;
ret = parse_btf_field(tmp, ctx->last_struct, pcode, end, ctx);
+ ctx->prefix_byteoffs = 0;
return ret;
}
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index f4fbe3010978..6a0859e00bf4 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -451,6 +451,7 @@ struct traceprobe_parse_context {
unsigned int flags;
int offset;
int nested_level;
+ int prefix_byteoffs; /* The byte offset of the prefix field of typecast */
};
/* Each typecast consumes nested level. So the max number of typecast is 3. */
@@ -594,7 +595,9 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(TYPECAST_NOT_EVENT, "Typecasts are only for eprobe fields"), \
C(TYPECAST_REQ_FIELD, "Typecast requires a field access"), \
C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"), \
- C(TYPECAST_SYM_OFFSET, "@SYM+/-OFFSET with typecast needs parentheses")
+ C(TYPECAST_SYM_OFFSET, "@SYM+/-OFFSET with typecast needs parentheses"), \
+ C(TYPECAST_NOT_ALIGNED, "Typecast field option is not byte-aligned"), \
+ C(TYPECAST_BAD_ARROW, "Typecast field option does not support -> operator"),
#undef C
#define C(a, b) TP_ERR_##a
^ permalink raw reply related
* [PATCH v13 09/11] tracing/probes: Add $current variable support
From: Masami Hiramatsu (Google) @ 2026-06-29 6:14 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Since we can use the BTF to cast value to a structure pointer type,
it is useful to introduce "$current" special variable support to
fetcharg.
User can define a fetcharg to access current task_struct properties
using BTF info. e.g.
$current->cpus_ptr
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v8:
- Avoid uninitialized ctx->btf issue on $current without typecast.
Changes in v7:
- Fix to use force-typecast for task_struct implicitly.
Changes in v6:
- Rebased on dump fetcharg patch.
- Remove function name/eprobe requirement for $current.
Changes in v5:
- Use s32 for bof_find_btf_id().
Changes in v4:
- Add $current in README when CONFIG_HAVE_FUNCTION_ARG_ACCESS_API=y case.
- Fix to prohibit using $current in eprobes and address based kprobes.
Changes in v3:
- Remove $current support from eprobes (because eprobes is only for event)
- Prohibit uprobes to use $current.
Changes in v2:
- Support to parse $current in parse_btf_arg().
- If no typecast on $current, it automatically casted to task_struct.
- Check error case if $current follows something except for "-".
---
Documentation/trace/fprobetrace.rst | 1 +
Documentation/trace/kprobetrace.rst | 1 +
kernel/trace/trace.c | 4 ++--
kernel/trace/trace_probe.c | 37 ++++++++++++++++++++++++++++++++++-
kernel/trace/trace_probe.h | 1 +
kernel/trace/trace_probe_tmpl.h | 3 +++
6 files changed, 44 insertions(+), 3 deletions(-)
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 290a9e6f7491..3392cab016b3 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -50,6 +50,7 @@ Synopsis of fprobe-events
$argN : Fetch the Nth function argument. (N >= 1) (\*2)
$retval : Fetch return value.(\*3)
$comm : Fetch current task comm.
+ $current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*4)(\*5)
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index a62707e6a9f2..81e4fe38791d 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -53,6 +53,7 @@ Synopsis of kprobe_events
$argN : Fetch the Nth function argument. (N >= 1) (\*1)
$retval : Fetch return value.(\*2)
$comm : Fetch current task comm.
+ $current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*3)(\*4)
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 5670c4b91dc0..2b0b4f9acb2e 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4320,13 +4320,13 @@ static const char readme_msg[] =
"\t args: <name>=fetcharg[:type]\n"
"\t fetcharg: (%<register>|$<efield>), @<address>, @<symbol>[+|-<offset>],\n"
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
- "\t $stack<index>, $stack, $retval, $comm, $arg<N>,\n"
+ "\t $stack<index>, $stack, $retval, $comm, $arg<N>, $current\n"
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
"\t [(structname[,field])]<argname>[->field[->field|.field...]],\n"
"\t [(structname[,field])](fetcharg)->field[->field|.field...],\n"
#endif
#else
- "\t $stack<index>, $stack, $retval, $comm,\n"
+ "\t $stack<index>, $stack, $retval, $comm, $current\n"
#endif
"\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
"\t kernel return probes support: $retval, $arg<N>, $comm\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index fd006b415c68..999dec84275d 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -692,7 +692,9 @@ static int parse_btf_arg(char *varname,
int i, is_ptr, ret;
u32 tid;
- if (!ctx->funcname && !(ctx->flags & TPARG_FL_TEVENT))
+ /* Note: field is not separated at this point, so check prefix. */
+ if (!str_has_prefix(varname, "$current") &&
+ !ctx->funcname && !(ctx->flags & TPARG_FL_TEVENT))
return -EINVAL;
is_ptr = split_next_field(varname, &field, ctx);
@@ -705,6 +707,20 @@ static int parse_btf_arg(char *varname,
return -EOPNOTSUPP;
}
+ if (!strcmp(varname, "$current")) {
+ code->op = FETCH_OP_CURRENT;
+ /* If no typecast is specified for $current, use task_struct by default */
+ ret = bpf_find_btf_id("task_struct", BTF_KIND_STRUCT, &ctx->struct_btf);
+ if (ret < 0) {
+ trace_probe_log_err(ctx->offset, NO_BTF_ENTRY);
+ return -ENOENT;
+ }
+ tid = (u32)ret;
+ type = ctx->last_struct =
+ btf_type_skip_modifiers(ctx->struct_btf, tid, NULL);
+ goto found_type;
+ }
+
if (ctx->flags & TPARG_FL_RETURN && !strcmp(varname, "$retval")) {
code->op = FETCH_OP_RETVAL;
/* Check whether the function return type is not void, even with typecast. */
@@ -761,6 +777,7 @@ static int parse_btf_arg(char *varname,
found:
type = btf_type_skip_modifiers(ctx->btf, tid, NULL);
+found_type:
if (!type) {
trace_probe_log_err(ctx->offset, BAD_BTF_TID);
return -EINVAL;
@@ -1270,6 +1287,24 @@ static int parse_probe_vars(char *orig_arg, const struct fetch_type *t,
return 0;
}
+ /* $current returns the address of the current task_struct. */
+ if (str_has_prefix(arg, "current")) {
+ /* $current is only supported by kernel probe. */
+ if (!(ctx->flags & TPARG_FL_KERNEL)) {
+ err = TP_ERR_BAD_VAR;
+ goto inval;
+ }
+ arg += strlen("current");
+ if (*arg == '-' && IS_ENABLED(CONFIG_PROBE_EVENTS_BTF_ARGS))
+ return parse_btf_arg(orig_arg, pcode, end, ctx);
+
+ if (*arg != '\0')
+ goto inval;
+
+ code->op = FETCH_OP_CURRENT;
+ return 0;
+ }
+
#ifdef CONFIG_HAVE_FUNCTION_ARG_ACCESS_API
len = str_has_prefix(arg, "arg");
if (len) {
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 6a0859e00bf4..195096f5b8b1 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -92,6 +92,7 @@ typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
FETCH_OP(RETVAL, none), /* Return value */ \
FETCH_OP(IMM, imm), /* Immediate: .immediate */ \
FETCH_OP(COMM, none), /* Current comm */ \
+ FETCH_OP(CURRENT, none), /* Current task_struct address */\
FETCH_OP(ARG, param), /* Argument: .param = index */ \
FETCH_OP(FOFFS, imm), /* File offset: .immediate */ \
FETCH_OP(IMMSTR, string), /* Allocated string: .data */ \
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index 51436f19083b..d0e9662cde00 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -112,6 +112,9 @@ process_common_fetch_insn(struct fetch_insn *code, unsigned long *val)
case FETCH_OP_IMMSTR:
*val = (unsigned long)code->data;
break;
+ case FETCH_OP_CURRENT:
+ *val = (unsigned long)current;
+ break;
default:
return -EILSEQ;
}
^ permalink raw reply related
* [PATCH v13 10/11] tracing/probes: Add this_cpu_read() and this_cpu_ptr() dereference method to fetcharg
From: Masami Hiramatsu (Google) @ 2026-06-29 6:14 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
When tracing the kernel local variables, sometimes we need to get the
CPU local variables. To access it, current simple dereference is not
enough.
Thus, introduce a special this_cpu_read() dereference to access per-cpu
variable for the current CPU (accessing other CPU variable may race with
updates on other CPUs). Also this_cpu_ptr() is for accessing per-cpu
pointer.
Those are working as same as the kernel percpu macro.
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v13:
- Remove missed comma fix from this patch.
Changes in v11:
- Remove this_cpu_*() from eprobetrace.rst.
Changes in v10:
- Prohibit this_cpu_*() for eprobe events.
Changes in v9:
- Prohibit this_cpu_*() for non kernel probes.
Changes in v6:
- Rebased on dump fetcharg patch.
- Fix to fetch static percpu variable with @SYM correctly.
Changes in v5:
- Simplify this_cpu_read() into +0(this_cpu_ptr()).
Changes in v3:
- Remove NULL check for percpu var because it is just an offset, could be 0.
- Simplify process_fetch_insn_bottom() code.
- If the last operation is this_cpu_read(), read only memory of the specific
size (of type).
Changes in v2:
- Drop +CPU/+PCPU and introduce this_cpu_read() and this_cpu_ptr().
- Support these method with BTF typecast.
- Just check the base address is NOT NULL instead of is_kernel_percpu_address().
---
Documentation/trace/fprobetrace.rst | 2
Documentation/trace/kprobetrace.rst | 2
kernel/trace/trace.c | 1
kernel/trace/trace_probe.c | 152 ++++++++++++++++++++++++++---------
kernel/trace/trace_probe.h | 4 +
kernel/trace/trace_probe_tmpl.h | 22 ++++-
6 files changed, 138 insertions(+), 45 deletions(-)
diff --git a/Documentation/trace/fprobetrace.rst b/Documentation/trace/fprobetrace.rst
index 3392cab016b3..3439bc9bd351 100644
--- a/Documentation/trace/fprobetrace.rst
+++ b/Documentation/trace/fprobetrace.rst
@@ -52,6 +52,8 @@ Synopsis of fprobe-events
$comm : Fetch current task comm.
$current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*4)(\*5)
+ this_cpu_read(FETCHARG) : Read the value of the per-CPU variable FETCHARG on the current CPU.
+ this_cpu_ptr(FETCHARG) : Get the address of the per-CPU variable FETCHARG on the current CPU.
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
diff --git a/Documentation/trace/kprobetrace.rst b/Documentation/trace/kprobetrace.rst
index 81e4fe38791d..9ae330eb0a52 100644
--- a/Documentation/trace/kprobetrace.rst
+++ b/Documentation/trace/kprobetrace.rst
@@ -55,6 +55,8 @@ Synopsis of kprobe_events
$comm : Fetch current task comm.
$current : Fetch the address of the current task_struct.
+|-[u]OFFS(FETCHARG) : Fetch memory at FETCHARG +|- OFFS address.(\*3)(\*4)
+ this_cpu_read(FETCHARG) : Read the value of the per-CPU variable FETCHARG on the current CPU.
+ this_cpu_ptr(FETCHARG) : Get the address of the per-CPU variable FETCHARG on the current CPU.
\IMM : Store an immediate value to the argument.
NAME=FETCHARG : Set NAME as the argument name of FETCHARG.
FETCHARG:TYPE : Set TYPE as the type of FETCHARG. Currently, basic types
diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c
index 2b0b4f9acb2e..c9e182d40059 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -4329,6 +4329,7 @@ static const char readme_msg[] =
"\t $stack<index>, $stack, $retval, $comm, $current\n"
#endif
"\t +|-[u]<offset>(<fetcharg>), \\imm-value, \\\"imm-string\"\n"
+ "\t this_cpu_read(<fetcharg>), this_cpu_ptr(<fetcharg>)\n"
"\t kernel return probes support: $retval, $arg<N>, $comm\n"
"\t type: s8/16/32/64, u8/16/32/64, x8/16/32/64, char, string, symbol,\n"
"\t b<bit-width>@<bit-offset>/<container-size>, ustring,\n"
diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c
index 999dec84275d..18c212122344 100644
--- a/kernel/trace/trace_probe.c
+++ b/kernel/trace/trace_probe.c
@@ -345,6 +345,109 @@ static int parse_trace_event(char *arg, struct fetch_insn *code,
return -EINVAL;
}
+/* this_cpu_* parser */
+#define THIS_CPU_PTR_PREFIX "this_cpu_ptr("
+#define THIS_CPU_READ_PREFIX "this_cpu_read("
+#define THIS_CPU_PTR_LEN (sizeof(THIS_CPU_PTR_PREFIX) - 1)
+#define THIS_CPU_READ_LEN (sizeof(THIS_CPU_READ_PREFIX) - 1)
+
+static int
+parse_probe_arg(char *arg, const struct fetch_type *type,
+ struct fetch_insn **pcode, struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx);
+
+/* handle dereference nested call */
+static inline int handle_dereference(char *arg, struct fetch_insn **pcode,
+ struct fetch_insn *end, struct traceprobe_parse_context *ctx,
+ int deref, long offset)
+{
+ const struct fetch_type *type = find_fetch_type(NULL, ctx->flags);
+ struct fetch_insn *code = *pcode;
+ int cur_offs = ctx->offset;
+ char *tmp;
+ int ret;
+
+ tmp = strrchr(arg, ')');
+ if (!tmp) {
+ trace_probe_log_err(ctx->offset + strlen(arg),
+ DEREF_OPEN_BRACE);
+ return -EINVAL;
+ }
+
+ *tmp = '\0';
+ ret = parse_probe_arg(arg, type, &code, end, ctx);
+ if (ret)
+ return ret;
+ ctx->offset = cur_offs;
+ if (code->op == FETCH_OP_COMM || code->op == FETCH_OP_IMMSTR) {
+ trace_probe_log_err(ctx->offset, COMM_CANT_DEREF);
+ return -EINVAL;
+ }
+
+ /*
+ * this_cpu_ptr(@SYM) does not use SYM value, but use SYM address.
+ * So we overwrite the last FETCH_OP_DEREF with FETCH_OP_CPU_PTR.
+ */
+ if (!(deref == FETCH_OP_CPU_PTR && *arg == '@')) {
+ code++;
+ if (code == end) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
+ return -EINVAL;
+ }
+ }
+ *pcode = code;
+
+ code->op = deref;
+ code->offset = offset;
+ /* Reset the last type if used */
+ ctx->last_type = NULL;
+ return 0;
+}
+
+static int parse_this_cpu(char *arg, struct fetch_insn **pcode,
+ struct fetch_insn *end,
+ struct traceprobe_parse_context *ctx)
+{
+ struct fetch_insn *code;
+ bool is_ptr = false;
+ int ret;
+
+ /*
+ * This is only for kernel probes, excluding eprobe, because per-cpu
+ * pointer should not be recorded by events.
+ */
+ if (!(ctx->flags & TPARG_FL_KERNEL) ||
+ (ctx->flags & TPARG_FL_TEVENT)) {
+ trace_probe_log_err(ctx->offset, NOSUP_PERCPU);
+ return -EINVAL;
+ }
+ if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX)) {
+ arg += THIS_CPU_PTR_LEN;
+ ctx->offset += THIS_CPU_PTR_LEN;
+ is_ptr = true;
+ } else if (str_has_prefix(arg, THIS_CPU_READ_PREFIX)) {
+ arg += THIS_CPU_READ_LEN;
+ ctx->offset += THIS_CPU_READ_LEN;
+ } else
+ return -EINVAL;
+
+ ret = handle_dereference(arg, pcode, end, ctx, FETCH_OP_CPU_PTR, 0);
+ if (ret || is_ptr)
+ return ret;
+
+ /* this_cpu_read(VAR) -> +0(this_cpu_ptr(VAR)) */
+ code = *pcode;
+ code++;
+ if (code == end) {
+ trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
+ return -EINVAL;
+ }
+ code->op = FETCH_OP_DEREF;
+ code->offset = 0;
+ *pcode = code;
+ return 0;
+}
+
#ifdef CONFIG_PROBE_EVENTS_BTF_ARGS
static u32 btf_type_int(const struct btf_type *t)
@@ -904,11 +1007,6 @@ static char *find_matched_close_paren(char *s)
return NULL;
}
-static int
-parse_probe_arg(char *arg, const struct fetch_type *type,
- struct fetch_insn **pcode, struct fetch_insn *end,
- struct traceprobe_parse_context *ctx);
-
static int handle_typecast(char *arg, struct fetch_insn **pcode,
struct fetch_insn *end,
struct traceprobe_parse_context *ctx)
@@ -961,7 +1059,9 @@ static int handle_typecast(char *arg, struct fetch_insn **pcode,
/* Skip '(' */
ctx->offset += 1;
tmp++;
- } else if (*tmp == '+' || *tmp == '-') {
+ } else if (*tmp == '+' || *tmp == '-' ||
+ str_has_prefix(tmp, THIS_CPU_PTR_PREFIX) ||
+ str_has_prefix(tmp, THIS_CPU_READ_PREFIX)) {
/* Dereference can have another field access inside it. */
char *open = strchr(tmp + 1, '(');
@@ -1481,36 +1581,9 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
}
ctx->offset += (tmp + 1 - arg) + (arg[0] != '-' ? 1 : 0);
arg = tmp + 1;
- tmp = strrchr(arg, ')');
- if (!tmp) {
- trace_probe_log_err(ctx->offset + strlen(arg),
- DEREF_OPEN_BRACE);
- return -EINVAL;
- } else {
- const struct fetch_type *t2 = find_fetch_type(NULL, ctx->flags);
- int cur_offs = ctx->offset;
-
- *tmp = '\0';
- ret = parse_probe_arg(arg, t2, &code, end, ctx);
- if (ret)
- break;
- ctx->offset = cur_offs;
- if (code->op == FETCH_OP_COMM ||
- code->op == FETCH_OP_IMMSTR) {
- trace_probe_log_err(ctx->offset, COMM_CANT_DEREF);
- return -EINVAL;
- }
- if (++code == end) {
- trace_probe_log_err(ctx->offset, TOO_MANY_OPS);
- return -EINVAL;
- }
- *pcode = code;
-
- code->op = deref;
- code->offset = offset;
- /* Reset the last type if used */
- ctx->last_type = NULL;
- }
+ ret = handle_dereference(arg, pcode, end, ctx, deref, offset);
+ if (ret < 0)
+ return ret;
break;
case '\\': /* Immediate value */
if (arg[1] == '"') { /* Immediate string */
@@ -1531,7 +1604,10 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
ret = handle_typecast(arg, pcode, end, ctx);
break;
default:
- if (isalpha(arg[0]) || arg[0] == '_') {
+ if (str_has_prefix(arg, THIS_CPU_PTR_PREFIX) ||
+ str_has_prefix(arg, THIS_CPU_READ_PREFIX)) {
+ ret = parse_this_cpu(arg, pcode, end, ctx);
+ } else if (isalpha(arg[0]) || arg[0] == '_') {
/* BTF variable or event field*/
if (ctx->flags & TPARG_FL_TEVENT) {
ret = parse_trace_event(arg, *pcode, ctx);
@@ -1548,8 +1624,8 @@ parse_probe_arg(char *arg, const struct fetch_type *type,
return -EINVAL;
}
ret = parse_btf_arg(arg, pcode, end, ctx);
- break;
}
+ break;
}
if (!ret && code->op == FETCH_OP_NOP) {
/* Parsed, but do not find fetch method */
diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h
index 195096f5b8b1..e6268a8dc378 100644
--- a/kernel/trace/trace_probe.h
+++ b/kernel/trace/trace_probe.h
@@ -101,6 +101,7 @@ typedef int (*print_type_func_t)(struct trace_seq *, void *, void *);
/* Stage 2 (dereference) ops */ \
FETCH_OP(DEREF, offset), /* Dereference: .offset */ \
FETCH_OP(UDEREF, offset), /* User-space dereference: .offset */\
+ FETCH_OP(CPU_PTR, none), /* Per-CPU pointer: .offset */ \
/* Stage 3 (store) ops */ \
FETCH_OP(ST_RAW, store), /* Raw value: .size */ \
FETCH_OP(ST_MEM, store), /* Memory: .offset, .size */ \
@@ -598,7 +599,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call,
C(TOO_MANY_NESTED, "Too many nested typecasts/dereferences"), \
C(TYPECAST_SYM_OFFSET, "@SYM+/-OFFSET with typecast needs parentheses"), \
C(TYPECAST_NOT_ALIGNED, "Typecast field option is not byte-aligned"), \
- C(TYPECAST_BAD_ARROW, "Typecast field option does not support -> operator"),
+ C(TYPECAST_BAD_ARROW, "Typecast field option does not support -> operator"), \
+ C(NOSUP_PERCPU, "Per-cpu variable access is only for kernel probes"),
#undef C
#define C(a, b) TP_ERR_##a
diff --git a/kernel/trace/trace_probe_tmpl.h b/kernel/trace/trace_probe_tmpl.h
index d0e9662cde00..8db12f758fda 100644
--- a/kernel/trace/trace_probe_tmpl.h
+++ b/kernel/trace/trace_probe_tmpl.h
@@ -129,25 +129,35 @@ process_fetch_insn_bottom(struct fetch_insn *code, unsigned long val,
struct fetch_insn *s3 = NULL;
int total = 0, ret = 0, i = 0;
u32 loc = 0;
- unsigned long lval = val;
+ unsigned long lval, llval = val;
stage2:
/* 2nd stage: dereference memory if needed */
do {
- if (code->op == FETCH_OP_DEREF) {
- lval = val;
+ lval = val;
+ switch (code->op) {
+ case FETCH_OP_DEREF:
ret = probe_mem_read(&val, (void *)val + code->offset,
sizeof(val));
- } else if (code->op == FETCH_OP_UDEREF) {
- lval = val;
+ break;
+ case FETCH_OP_UDEREF:
ret = probe_mem_read_user(&val,
(void *)val + code->offset, sizeof(val));
- } else
break;
+ case FETCH_OP_CPU_PTR:
+ val = (unsigned long)this_cpu_ptr((void __percpu *)val);
+ ret = 0;
+ break;
+ default:
+ lval = llval;
+ goto out;
+ }
if (ret)
return ret;
+ llval = lval;
code++;
} while (1);
+out:
s3 = code;
stage3:
^ permalink raw reply related
* [PATCH v13 11/11] tracing/probes: Add a new testcase for BTF typecasts
From: Masami Hiramatsu (Google) @ 2026-06-29 6:14 UTC (permalink / raw)
To: Steven Rostedt, Mathieu Desnoyers
Cc: Jonathan Corbet, Shuah Khan, Masami Hiramatsu, linux-kernel,
linux-trace-kernel, linux-doc, linux-kselftest
In-Reply-To: <178271357142.1176915.7193483024740701480.stgit@devnote2>
From: Masami Hiramatsu (Google) <mhiramat@kernel.org>
With the introduction of container_of-style BTF typecasting and
per-CPU variable access support in trace probes, we need a way to
verify their functionality and prevent regressions.
Add a new ftrace kselftest and update the trace event sample module
to test and validate these features.
Specifically, update the trace-events-sample module to set up a
periodic timer whose callback accesses a per-CPU counter. Introduce
a new sample trace event, foo_timer_fn, to trace this callback
and log the current counter value.
Then, add a new test case, btf_probe_event.tc, which defines a
dynamic probe on the timer callback. The probe uses BTF typecasting
to recover the parent structure from the timer argument and
this_cpu_read() to fetch the per-CPU counter. The test verifies
the integrity of the implementation by ensuring the values
recorded by the dynamic probe match those from the static tracepoint.
Assisted-by: Antigravity:gemini-3.5-flash
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
---
Changes in v12:
- Fix current support check in eprobe testcase.
- Fix to return UNRESOLVED error if sample module is not found.
- Always check this_cpu_* in btf_typecast_accepted.tc.
Changes in v11:
- nit: fix the error code in comment.
Changes in v10:
- Add a check for $current and this_cpu_* for eprobe
Changes in v9:
- Add a testcase for checking new syntax.
Changes in v8:
- Add more test cases.
Changes in v6:
- Update testcase according to changes.
Changes in v5:
- Add more syntax test cases.
Changes in v4:
- Fix uprobe $current test.
Changes in v3:
- Add syntax test case.
- Update testcase to use this_cpu_read()
Changes in v2:
- Use timer_shutdown_sync() instead of timer_delete_sync() for teardown.
---
samples/trace_events/trace-events-sample.c | 40 +++++++-
samples/trace_events/trace-events-sample.h | 34 ++++++-
.../ftrace/test.d/dynevent/btf_probe_event.tc | 51 ++++++++++
.../test.d/dynevent/btf_typecast_accepted.tc | 103 ++++++++++++++++++++
.../test.d/dynevent/eprobes_syntax_errors.tc | 9 ++
.../ftrace/test.d/dynevent/fprobe_syntax_errors.tc | 12 ++
.../ftrace/test.d/kprobe/kprobe_syntax_errors.tc | 12 ++
.../ftrace/test.d/kprobe/uprobe_syntax_errors.tc | 5 +
8 files changed, 261 insertions(+), 5 deletions(-)
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
create mode 100644 tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
diff --git a/samples/trace_events/trace-events-sample.c b/samples/trace_events/trace-events-sample.c
index 0b7a6efdb247..ca5d98c360cb 100644
--- a/samples/trace_events/trace-events-sample.c
+++ b/samples/trace_events/trace-events-sample.c
@@ -94,6 +94,20 @@ static int simple_thread_fn(void *arg)
static DEFINE_MUTEX(thread_mutex);
static int simple_thread_cnt;
+static struct foo_timer_data *foo_timer_data;
+
+static void sample_timer_cb(struct timer_list *t)
+{
+ struct foo_timer_data *data = container_of(t, struct foo_timer_data, timer);
+
+ get_cpu();
+ trace_foo_timer_fn(data);
+ (*this_cpu_ptr(data->counter))++;
+ put_cpu();
+
+ mod_timer(t, jiffies + HZ);
+}
+
int foo_bar_reg(void)
{
mutex_lock(&thread_mutex);
@@ -132,9 +146,27 @@ void foo_bar_unreg(void)
static int __init trace_event_init(void)
{
+ foo_timer_data = kzalloc_obj(*foo_timer_data, GFP_KERNEL);
+ if (!foo_timer_data)
+ return -ENOMEM;
+
+ foo_timer_data->name = "sample_timer_counter";
+ foo_timer_data->counter = alloc_percpu(int);
+ if (!foo_timer_data->counter) {
+ kfree(foo_timer_data);
+ return -ENOMEM;
+ }
+
+ timer_setup(&foo_timer_data->timer, sample_timer_cb, 0);
+ mod_timer(&foo_timer_data->timer, jiffies + HZ);
+
simple_tsk = kthread_run(simple_thread, NULL, "event-sample");
- if (IS_ERR(simple_tsk))
- return -1;
+ if (IS_ERR(simple_tsk)) {
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
+ return PTR_ERR(simple_tsk);
+ }
return 0;
}
@@ -147,6 +179,10 @@ static void __exit trace_event_exit(void)
kthread_stop(simple_tsk_fn);
simple_tsk_fn = NULL;
mutex_unlock(&thread_mutex);
+
+ timer_shutdown_sync(&foo_timer_data->timer);
+ free_percpu(foo_timer_data->counter);
+ kfree(foo_timer_data);
}
module_init(trace_event_init);
diff --git a/samples/trace_events/trace-events-sample.h b/samples/trace_events/trace-events-sample.h
index 1a05fc153353..816848a456a2 100644
--- a/samples/trace_events/trace-events-sample.h
+++ b/samples/trace_events/trace-events-sample.h
@@ -247,12 +247,14 @@
*/
/*
- * It is OK to have helper functions in the file, but they need to be protected
- * from being defined more than once. Remember, this file gets included more
- * than once.
+ * It is OK to have helper functions and data structures in the file, but they
+ * need to be protected from being defined more than once. Remember, this file
+ * gets included more than once.
*/
#ifndef __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
#define __TRACE_EVENT_SAMPLE_HELPER_FUNCTIONS
+#include <linux/timer.h>
+
static inline int __length_of(const int *list)
{
int i;
@@ -270,6 +272,13 @@ enum {
TRACE_SAMPLE_BAR = 4,
TRACE_SAMPLE_ZOO = 8,
};
+
+struct foo_timer_data {
+ const char *name;
+ struct timer_list timer;
+ int __percpu *counter;
+};
+
#endif
/*
@@ -595,6 +604,25 @@ TRACE_EVENT(foo_rel_loc,
__get_rel_bitmask(bitmask),
__get_rel_cpumask(cpumask))
);
+
+TRACE_EVENT(foo_timer_fn,
+
+ TP_PROTO(struct foo_timer_data *data),
+
+ TP_ARGS(data),
+
+ TP_STRUCT__entry(
+ __string( name, data->name )
+ __field( int, count )
+ ),
+
+ TP_fast_assign(
+ __assign_str(name);
+ __entry->count = *this_cpu_ptr(data->counter);
+ ),
+
+ TP_printk("name=%s count=%d", __get_str(name), __entry->count)
+);
#endif
/***** NOTICE! The #if protection ends here. *****/
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
new file mode 100644
index 000000000000..bf71368c31a4
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/btf_probe_event.tc
@@ -0,0 +1,51 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: BTF event with typecast and percpu access
+# requires: dynamic_events "this_cpu_read(<fetcharg>)":README "[(structname[,field])]<argname>[->field[->field|.field...]]":README
+
+# Check if the sample module is loaded
+if ! lsmod | grep -q trace_events_sample; then
+ modprobe trace-events-sample || exit_unresolved
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# The sample_timer_cb(struct timer_list *t) is called.
+# We want to check (STRUCT,FIELD)VAR typecast and this_cpu_read() access.
+# (foo_timer_data,timer)t converts t to struct foo_timer_data * using container_of.
+# data->counter is a per-cpu pointer to int.
+# this_cpu_read(data->counter) should give the value of the counter.
+
+echo 'f:mysample/myevent sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+
+echo 1 > events/mysample/myevent/enable
+echo 1 > events/sample-trace/foo_timer_fn/enable
+
+sleep 2
+
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+
+# Compare the values.
+MATCH=0
+while read line; do
+ if echo $line | grep -q "foo_timer_fn:"; then
+ NAME=`echo $line | sed 's/.*name=\([^ ]*\) .*/\1/'`
+ COUNT=`echo $line | sed 's/.*count=\([^ ]*\).*/\1/'`
+ if grep -q "myevent:.*name=\"${NAME}\" count=$COUNT" trace; then
+ MATCH=$((MATCH+1))
+ fi
+ fi
+done < trace
+
+if [ $MATCH -eq 0 ]; then
+ echo "No matching events found"
+ exit_fail
+fi
+
+# Clean up
+echo 0 > events/mysample/myevent/enable
+echo 0 > events/sample-trace/foo_timer_fn/enable
+echo > dynamic_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc b/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
new file mode 100644
index 000000000000..dd5552727054
--- /dev/null
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/btf_typecast_accepted.tc
@@ -0,0 +1,103 @@
+#!/bin/sh
+# SPDX-License-Identifier: GPL-2.0
+# description: BTF typecast and percpu access syntax validation
+# requires: dynamic_events "this_cpu_read(<fetcharg>)":README "[(structname[,field])]<argname>[->field[->field|.field...]]":README
+
+KPROBES=
+FPROBES=
+
+if grep -qF "p[:[<group>/][<event>]] <place> [<args>]" README ; then
+ KPROBES=yes
+fi
+if grep -qF "f[:[<group>/][<event>]] <func-name>[%return] [<args>]" README ; then
+ FPROBES=yes
+fi
+
+if [ -z "$KPROBES" -a -z "$FPROBES" ] ; then
+ exit_unsupported
+fi
+
+echo 0 > events/enable
+echo > dynamic_events
+
+# Load trace-events-sample module if available to have per-CPU counter structure defined
+if ! lsmod | grep -q trace_events_sample; then
+ modprobe trace-events-sample || exit_unresolved
+fi
+
+if [ "$FPROBES" ] ; then
+ # 1. Test basic typecast on fprobe
+ echo 'f:fpevent1 vfs_read name=(file)file->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 2. Test parenthesized typecast target on fprobe
+ echo 'f:fpevent2 vfs_read name=(file)(file)->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 3. Test nested typecasts on fprobe
+ echo 'f:fpevent3 vfs_read name=(dentry)((file)file->f_path.dentry)->d_name.name:string' >> dynamic_events
+ # 4. Test container_of-style typecast with field option on fprobe
+ echo 'f:fpevent4 vfs_read name=(file,f_path)file->f_mode' >> dynamic_events
+ # 5. Test typecast on return value on fprobe
+ echo 'f:fpevent5 vfs_read%return name=(file)$retval->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 6. Test $current variable support on fprobe
+ echo 'f:fpevent6 vfs_read pid=$current->pid' >> dynamic_events
+ echo 'f:fpevent7 vfs_read pid=(task_struct)$current->pid' >> dynamic_events
+ echo 'f:fpevent8 vfs_read pid=(task_struct,group_leader)$current->pid' >> dynamic_events
+
+ # Test this_cpu_read and this_cpu_ptr on fprobe
+ echo 'f:fpevent9 sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+ echo 'f:fpevent10 sample_timer_cb ptr=this_cpu_ptr((foo_timer_data,timer)t->counter)' >> dynamic_events
+fi
+
+if [ "$KPROBES" ] ; then
+ # 7. Test basic typecast on kprobe
+ echo 'p:kpevent1 vfs_read name=(file)file->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 8. Test parenthesized typecast target on kprobe
+ echo 'p:kpevent2 vfs_read name=(file)(file)->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 9. Test nested typecasts on kprobe
+ echo 'p:kpevent3 vfs_read name=(dentry)((file)file->f_path.dentry)->d_name.name:string' >> dynamic_events
+ # 10. Test container_of-style typecast with field option on kprobe
+ echo 'p:kpevent4 vfs_read name=(file,f_path)file->f_mode' >> dynamic_events
+ # 11. Test typecast on return value on kretprobe
+ echo 'r:kpevent5 vfs_read name=(file)$retval->f_path.dentry->d_name.name:string' >> dynamic_events
+ # 12. Test $current variable support on kprobe
+ echo 'p:kpevent6 vfs_read pid=$current->pid' >> dynamic_events
+ echo 'p:kpevent7 vfs_read pid=(task_struct)$current->pid' >> dynamic_events
+ echo 'p:kpevent8 vfs_read pid=(task_struct,group_leader)$current->pid' >> dynamic_events
+
+ # Test this_cpu_read and this_cpu_ptr on kprobe
+ echo 'p:kpevent9 sample_timer_cb name=(foo_timer_data,timer)t->name:string count=this_cpu_read((foo_timer_data,timer)t->counter)' >> dynamic_events
+ echo 'p:kpevent10 sample_timer_cb ptr=this_cpu_ptr((foo_timer_data,timer)t->counter)' >> dynamic_events
+fi
+
+# Verify the events exist in dynamic_events
+if [ "$FPROBES" ] ; then
+ grep -q "fpevent1 " dynamic_events
+ grep -q "fpevent2 " dynamic_events
+ grep -q "fpevent3 " dynamic_events
+ grep -q "fpevent4 " dynamic_events
+ grep -q "fpevent5 " dynamic_events
+ grep -q "fpevent6 " dynamic_events
+ grep -q "fpevent7 " dynamic_events
+ grep -q "fpevent8 " dynamic_events
+ if lsmod | grep -q trace_events_sample; then
+ grep -q "fpevent9 " dynamic_events
+ grep -q "fpevent10 " dynamic_events
+ fi
+fi
+
+if [ "$KPROBES" ] ; then
+ grep -q "kpevent1 " dynamic_events
+ grep -q "kpevent2 " dynamic_events
+ grep -q "kpevent3 " dynamic_events
+ grep -q "kpevent4 " dynamic_events
+ grep -q "kpevent5 " dynamic_events
+ grep -q "kpevent6 " dynamic_events
+ grep -q "kpevent7 " dynamic_events
+ grep -q "kpevent8 " dynamic_events
+ if lsmod | grep -q trace_events_sample; then
+ grep -q "kpevent9 " dynamic_events
+ grep -q "kpevent10 " dynamic_events
+ fi
+fi
+
+# Clean up
+echo > dynamic_events
+clear_trace
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
index 0e65e787e426..c2e3f9d19f13 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/eprobes_syntax_errors.tc
@@ -21,8 +21,17 @@ check_error 'e:foo/^bar.1 syscalls/sys_enter_openat' # BAD_EVENT_NAME
check_error 'e:foo/bar syscalls/sys_enter_openat arg=^$foo' # BAD_ATTACH_ARG
+check_error 'e:foo/bar syscalls/sys_enter_openat arg=^COMM' # NO_EVENT_FIELD
+if grep -q "\$current.*" README; then
+ check_error 'e:foo/bar syscalls/sys_enter_openat arg=^current' # NO_EVENT_FIELD
+fi
+
if grep -q '<attached-group>\.<attached-event>.*\[if <filter>\]' README; then
check_error 'e:foo/bar syscalls/sys_enter_openat if ^' # NO_EP_FILTER
fi
+if grep -q 'this_cpu_read(<fetcharg>)' README; then
+ check_error 'e:foo/bar syscalls/sys_enter_openat arg=^this_cpu_read(file)' # NOSUP_PERCPU
+fi
+
exit 0
diff --git a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
index fee479295e2f..e9d7e6919c7f 100644
--- a/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/dynevent/fprobe_syntax_errors.tc
@@ -112,6 +112,18 @@ check_error 'f vfs_read%return $retval->^foo' # NO_PTR_STRCT
check_error 'f vfs_read file->^foo' # NO_BTF_FIELD
check_error 'f vfs_read file^-.foo' # BAD_HYPHEN
check_error 'f vfs_read ^file:string' # BAD_TYPE4STR
+if grep -qF "[(structname" README ; then
+check_error 'f vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'f vfs_read arg1=(a)((b)((c)(^(d)file->d)->c)->b)->a' # TOO_MANY_NESTED
+check_error 'f vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'f vfs_read arg1=(task_struct,^foo_bar)file->pid' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(^task_struct1234)file->pid' # NO_PTR_STRCT
+check_error 'f vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'f vfs_read arg1=(task_struct,^->pid)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct,^.pid)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct,^.)file->comm' # NO_BTF_FIELD
+check_error 'f vfs_read arg1=(task_struct)^@symbol+10->comm' # TYPECAST_SYM_OFFSET
+fi
fi
else
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
index 8f1c58f0c239..21ce8414459f 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/kprobe_syntax_errors.tc
@@ -115,6 +115,18 @@ check_error 'p vfs_read+20 ^$arg*' # NOFENTRY_ARGS
check_error 'p vfs_read ^hoge' # NO_BTFARG
check_error 'p kfree ^$arg10' # NO_BTFARG (exceed the number of parameters)
check_error 'r kfree ^$retval' # NO_RETVAL
+if grep -qF "[(structname" README ; then
+check_error 'p vfs_read arg1=(task_struct)file^' # TYPECAST_REQ_FIELD
+check_error 'p vfs_read arg1=(a)((b)((c)(^(d)file->d)->c)->b)->a' # TOO_MANY_NESTED
+check_error 'p vfs_read arg1=(task_struct,^in_execve)file->comm' # TYPECAST_NOT_ALIGNED
+check_error 'p vfs_read arg1=(task_struct,^foo_bar)file->pid' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(^task_struct1234)file->pid' # NO_PTR_STRCT
+check_error 'p vfs_read arg1=(task_struct,se^->group_node)file->comm' # TYPECAST_BAD_ARROW
+check_error 'p vfs_read arg1=(task_struct,^->pid)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct,^.pid)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct,^.)file->comm' # NO_BTF_FIELD
+check_error 'p vfs_read arg1=(task_struct)^@symbol+10->comm' # TYPECAST_SYM_OFFSET
+fi
else
check_error 'p vfs_read ^$arg*' # NOSUP_BTFARG
fi
diff --git a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
index c817158b99db..e12dc967ec76 100644
--- a/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
+++ b/tools/testing/selftests/ftrace/test.d/kprobe/uprobe_syntax_errors.tc
@@ -28,4 +28,9 @@ if grep -q ".*symstr.*" README; then
check_error 'p /bin/sh:10 $stack0:^symstr' # BAD_TYPE
fi
+# $current is not supported by uprobe
+if grep -q "\$current.*" README; then
+check_error 'p /bin/sh:10 ^$current:u8' # BAD_VAR
+fi
+
exit 0
^ permalink raw reply related
* Re: [PATCH] docs/mm: Fix brackets
From: David Hildenbrand (Arm) @ 2026-06-29 6:34 UTC (permalink / raw)
To: Manuel Ebner, Jason Gunthorpe, Leon Romanovsky, Andrew Morton,
Lorenzo Stoakes, Liam R . Howlett, Vlastimil Babka, Mike Rapoport,
Suren Baghdasaryan, Michal Hocko, Jonathan Corbet, Shuah Khan,
Shakeel Butt, open list:HMM - Heterogeneous Memory Management,
open list:DOCUMENTATION, open list
In-Reply-To: <20260627093258.31265-2-manuelebner@mailbox.org>
On 6/27/26 11:32, Manuel Ebner wrote:
> Remove unnecessary ')' and missing '('.
Insert empty line here.
> Signed-off-by: Manuel Ebner <manuelebner@mailbox.org>
> ---
> Documentation/mm/hmm.rst | 4 ++--
> Documentation/mm/process_addrs.rst | 2 +-
> 2 files changed, 3 insertions(+), 3 deletions(-)
>
> diff --git a/Documentation/mm/hmm.rst b/Documentation/mm/hmm.rst
> index 7d61b7a8b65b..54c461e7a143 100644
> --- a/Documentation/mm/hmm.rst
> +++ b/Documentation/mm/hmm.rst
> @@ -191,7 +191,7 @@ like a CPU page fault. The usage pattern is::
> mmap_read_unlock(mm);
>
> take_lock(driver->update);
> - if (mmu_interval_read_retry(&ni, range.notifier_seq) {
> + if (mmu_interval_read_retry(&ni, range.notifier_seq)) {
Adding missing ")"
> release_lock(driver->update);
> goto again;
> }
> @@ -316,7 +316,7 @@ between device driver specific code and shared common code:
> system memory and device private memory.
>
> One of the first steps migrate_vma_setup() does is to invalidate other
> - device's MMUs with the ``mmu_notifier_invalidate_range_start(()`` and
> + device's MMUs with the ``mmu_notifier_invalidate_range_start()`` and
Removing unnecessary "("
> ``mmu_notifier_invalidate_range_end()`` calls around the page table
> walks to fill in the ``args->src`` array with PFNs to be migrated.
> The ``invalidate_range_start()`` callback is passed a
> diff --git a/Documentation/mm/process_addrs.rst b/Documentation/mm/process_addrs.rst
> index 851680ead45f..b391502fbfd6 100644
> --- a/Documentation/mm/process_addrs.rst
> +++ b/Documentation/mm/process_addrs.rst
> @@ -724,7 +724,7 @@ the zap and the invocation of :c:func:`!free_pgtables`.
>
> Since it is assumed that all such steps have been taken, page table entries are
> cleared without page table locks (in the :c:func:`!pgd_clear`, :c:func:`!p4d_clear`,
> -:c:func:`!pud_clear`, and :c:func:`!pmd_clear` functions.
> +:c:func:`!pud_clear`, and :c:func:`!pmd_clear` functions).
Adding missing ")".
So your patch description is not quite correct? :)
--
Cheers,
David
^ permalink raw reply
* Re: [PATCH 2/5] dt-bindings: firmware: svc: add hwmon property
From: NG, TZE YEE @ 2026-06-29 6:36 UTC (permalink / raw)
To: Krzysztof Kozlowski
Cc: Guenter Roeck, Rob Herring, Krzysztof Kozlowski, Conor Dooley,
linux-hwmon@vger.kernel.org, devicetree@vger.kernel.org,
linux-kernel@vger.kernel.org, Dinh Nguyen, Rao, Mahesh,
Jonathan Corbet, Shuah Khan, linux-doc@vger.kernel.org
In-Reply-To: <20260622-straight-honest-cuttlefish-1a88fb@quoll>
On 22/6/2026 10:05 pm, Krzysztof Kozlowski wrote:
> On Fri, Jun 19, 2026 at 02:38:53AM -0700, tze.yee.ng@altera.com wrote:
>> From: Tze Yee Ng <tze.yee.ng@altera.com>
>>
>> Altera Stratix 10 SoCFPGA supports hardware monitor access through the
>> service layer mailbox. Add an optional hwmon child node to the service
>> layer binding so device trees can describe the hardware monitor.
>>
>> Signed-off-by: Nazim Amirul <muhammad.nazim.amirul.nazle.asmade@altera.com>
>> Signed-off-by: Tze Yee Ng <tze.yee.ng@altera.com>
>> ---
>> .../devicetree/bindings/firmware/intel,stratix10-svc.yaml | 4 ++++
>> 1 file changed, 4 insertions(+)
>>
>> diff --git a/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml b/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> index b42cfa78b28b..86ffdb10132f 100644
>> --- a/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> +++ b/Documentation/devicetree/bindings/firmware/intel,stratix10-svc.yaml
>> @@ -62,6 +62,10 @@ properties:
>> $ref: /schemas/fpga/intel,stratix10-soc-fpga-mgr.yaml
>> description: Optional child node for fpga manager to perform fabric configuration.
>>
>> + hwmon:
>> + $ref: /schemas/hwmon/altr,stratix10-hwmon.yaml
>
> So hwmon is completely fake wrapper over two other wrappers... If in
> doubts, please read slides from DTS101 presentations from OSS, including
> the chapter about Linux driver design.
>
> Best regards,
> Krzysztof
>
Hi Krzystof,
Thanks for review.
You pointed out that the hwmon DT binding was not appropriate because
this is not a discrete hardware block with its own MMIO/IRQ resources. I
agree with that assessment.
In v2, we will remove the hwmon device tree binding entirely:
- There is no compatible string for the hwmon driver.
- There is no hwmon child node under the service layer in DTS.
- stratix10-svc registers a socfpga-hwmon platform device when
CONFIG_SENSORS_ALTERA_SOCFPGA_HWMON is enabled, similar to how it
already registers stratix10-rsu.
- The hwmon driver binds by platform device name only.
- Sensor channels are selected from hardcoded tables based on the parent
service layer of_node compatible (intel,stratix10-svc or intel,agilex-svc).
Thanks,
Tze Yee
^ permalink raw reply
* [PATCH v26 0/7] firmware: imx: driver for NXP secure-enclave
From: pankaj.gupta @ 2026-06-29 12:21 UTC (permalink / raw)
To: Jonathan Corbet, Shuah Khan, Rob Herring, Krzysztof Kozlowski,
Conor Dooley, Frank Li, Sascha Hauer, Pengutronix Kernel Team,
Fabio Estevam, Pankaj Gupta
Cc: linux-doc, linux-kernel, devicetree, imx, linux-arm-kernel,
Frieder Schrempf, kernel test robot, sashiko-bot
The NXP's i.MX EdgeLock Enclave, a HW IP creating an embedded secure
enclave within the SoC boundary to enable features like
- HSM
- SHE
- V2X
Communicates via message unit with linux kernel. This driver is
enables communication ensuring well defined message sequence protocol
between Application Core and enclave's firmware.
Driver configures multiple misc-device on the MU, for multiple
user-space applications can communicate on single MU.
It exists on some i.MX processors. e.g. i.MX8ULP, i.MX93 etc.
-------
Changes in v26:
- Folded kernel test robot and Sashiko-bot fixes into the series.
- Added MAILBOX dependency for COMPILE_TEST builds.
- Hardened response waiter timeout handling and late-response processing.
- Serialized command receiver registration and callback-visible receiver state.
- Added iobuf round_up() overflow detection.
- Rolled back iobuf shared-memory reservation on setup failures.
- Bounded userspace-controlled response buffer size.
- Preserved ioctl operation errors across cleanup.
- Added explicit priv/dev_ctx lifetime handling and teardown/open serialization.
Testing:
- checkpatch.pl --strict: no warnings
- sparse: no warnings
- coccicheck on drivers/firmware/imx/: no driver-specific warnings
Reference:
- Link to v25: https://lore.kernel.org/r/20260122-imx-se-if-v25-0-5c3e3e3b69a8@nxp.com
Changes in v25:
5/7
- removes kernel bot reported warning errors.
3/7
- fix checkpatch --strict error.
1/2, 2/7, 4/7, 6/7 & 7/7
- No changes
Reference:
- Link to v24: https://lore.kernel.org/r/20260121-imx-se-if-v24-0-c5222df51cc2@nxp.com
Changes in v24:
5/7 & 3/7
- removes kernel bot reported warning errors.
1/2, 2/7, 4/7, 6/7 & 7/7
- No changes
Reference:
- Link to v23: https://lore.kernel.org/r/20251219-imx-se-if-v23-0-5c6773d00318@nxp.com
Changes in v23:
5/7
- removed un-neccessary 'kfree' from the func se_ioctl_cmd_snd_rcv_rsp_handler().
1/2, 2/7, 3/7, 4/7, 6/7 & 7/7
- No changes
Reference:
- Link to v22: https://lore.kernel.org/r/20251218-imx-se-if-v22-0-07418c872509@nxp.com
Changes in v22:
3/7 & 5/7
- reverted to previous change of using "__free(kfree)", by declare-and-initialize __free() vars next to their allocations.
1/7
- rename the se_fw.c to se_ctrl.c
2/7, 4/7, 5/7 & 7/7
- No changes.
Reference:
- Link to v21: https://lore.kernel.org/r/20251212-imx-se-if-v21-0-ee7d6052d848@nxp.com
Changes in v21:
3/7
- smatch warning fixes.
- Added "COMPILE_TEST" into "depends on IMX_MBOX && ARCH_MXC && ARM64"
- removed "__free(kfree)" & added kfree();
5/7
- removed "__free(kfree)" & added kfree();
1/2, 2/7, 4/7, & 7/7
- No changes
Reference:
- Link to v20: https://lore.kernel.org/r/20251203-imx-se-if-v20-0-a04a25c4255f@nxp.com
Changes in v20:
5/7:
- adds a func "se_chk_tx_msg_hdr", to check the validity of the in-coming message from usersapce.
1/2, 2/7, 3/7, 4/7, 6/7 & 7/7
- No changes
Reference:
- Link to v19: https://lore.kernel.org/r/20250927-imx-se-if-v19-0-d1e7e960c118@nxp.com
Changes in v19:
1/7
- Added 9 lines to the Introduction from line 73-82.
3/7
- Update the commit message for " For i.MX9x SoC(s) there is at least one
dedicated ELE MU(s) for each world - Linux(one or more) and OP-TEE OS (one or
more), that needs to be shared between them.."
Reference:
- Link to v18: https://lore.kernel.org/r/20250619-imx-se-if-v18-0-c98391ba446d@nxp.com
Changes in v18:
1/7
- Wrap both diagrams above in literal code block by using double-colon
3/7 & 5/7
- Collected Frank's R-b tag.
2/7, 4/7, 6/7 & 7/7
- No changes
Reference:
- Link to v17: https://lore.kernel.org/r/20250426-imx-se-if-v17-0-0c85155a50d1@nxp.com
Changes in v17:
- Changes to 3/7 & 5/7: to wrap code text at 80 character whereever possible.
Reference:
- Link to v16: https://lore.kernel.org/r/20250409-imx-se-if-v16-0-5394e5f3417e@nxp.com
Changes in v16:
- commit 3/7 and 4/7 are moved to end commits making them as 6/7 and 7/7 respectively.
- No change in 1/7 & 2/7.
7/7
- Collected Frank's R-b tag.
6/7
- commit message is updated to wrap at 75 characters.
5/7
- func add_b_desc_to_pending_list, removed the initialization of b_desc to
NULL.
- variable timeout in func ele_msg_rcv(), is renamed to timeout_ms.
- struct se_if_priv, member variable se_rcv_msg_timeout, is renamed to
se_rcv_msg_timeout_ms.
- in func load_firmware, move the label exit after dma_free_coherent.
4/7
- commit message is updated to wrap at 75 characters.
3/7
- ele_debug_dump, updated the assignment of keep_logging.
- ele_fw_authenticate function definition is updated to take two address
as arguments.
Reference:
- Link to v15: https://lore.kernel.org/r/20250407-imx-se-if-v15-0-e3382cecda01@nxp.com
Changes in v15:
- Patch 3/6 is split into two:
- 3/7: arm64: dts: imx8ulp-evk: add reserved memory property
- 4/7: arm64: dts: imx8ulp: add nxp secure enclave firmware
- No change in 1/7 & 2/7.
7/7
- removed the se_intance_id structure member variable.
- replace variable name from wait to timeout.
- used 'goto' to follow the common exit path calling "release_firmware(fw);" in case of error path.
- removed TBD string.
- Used ARRAY_SIZE(pending_lists).
- moved init_device_context after init_misc_device_context.
- defined err as long to avoid force convert in func
- added se_rcv_msg_timeout to priv, to control probe/suspend/resume per interface.
6/7
- removed the se_intance_id structure member variable.
- Added dev_ctx to the structure se_clbk_handle, too.
- Collected Frank's R-b tag.
5/7
- removed the se_intance_id structure member variable.
- since added se_if_probe_cleanup to devm, se_if_remove() is redundant. hence removed it.
- rename se_add_msg_chksum to se_get_msg_chksum
- added check if msg-size is 4 byte aligned.
- Fixed multiline comments.
- ele_debug_dump api is updated as part of comment disposition like single setting of flag "keep_logging" & adding if (ret).
- moved dev_err to dev_dbg, for imem save/restore functions.
- moved func get_se_if_name, from 7/7 to here.
3/7
- Updated the commit message.
- split the current patch into two:
-- 3/7 for board dts, and
-- 4/7 for chip dts
Reference:
- Link to v14: https://lore.kernel.org/r/20250327-imx-se-if-v14-0-2219448932e4@nxp.com
Changes in v14:
- Patch 5/5 is split into two:
- firmware: drivers: imx: adds miscdev
- Introduce dev-ctx dedicated to private.
-- Base patch before enabling misc-device context, to have the send-receive path, based on device context.
- No change in 1/6 & 2/6.
- Copied change logs from individual commits.
6/6
- moved definition of func se_load_firmware, from 4/6 patch to this patch.
- split init_device_context to init_misc_device_context.
- Different value of se_rcv_msg_timeout is required to be set. Receiving the response of 4K RSA operation can to take upto 3 minutes.
This long value cannot be set during Linux: boot-up and suspend-resume.
Hence, it will be set to default small-value during Linux: boot-up and suspend-resume.
- func se_dev_ctx_cpy_out_data(), in either case: do_cpy true or false, the clean-up needs to be done and it is implemented like wise.
Once do_cpy is false, no need to continue copy to user buffer. But continue to do clean-up. hence cannot return.
And every dev-ctx operation is done after taking the lock. Hence, two operations with same dev-ctx is not possible in parallel.
- func "init_device_context", for 0th misc dev_ctx, which is created at the time of probe, the device memory management is required. hence there is a difference.
- func "init_device_context", dev_er is replaced with return dev_err_probe.
- func "init_device_context", devm_add_action is replaced by devm_add_action_reset.
- removed type-cast from func se_ioctl_get_se_soc_info_handler().
- used scoped_cond_guard(mutex, _intr, return -EBUSY, &<mutex_lock>)
- combined dev_err & dev_dbg to one dev_err in se_if_fops_read().
- removed the structure member "se_shared_mem_mgmt->secure_mem".
4/6
- trimmed the ele_fetch_soc_info.
- removed the function ptr "se_info->se_fetch_soc_info" and replaced with ele_fetch_soc_info.
- moved definition of func se_load_firmware, to 6/6 patch.
- Different SoC, different ways to fetch soc_info. Generic function declaration for ele_fetch_soc_info() is needed. Hence wrapping ele_get_info() in it.
- Updated Kconfig help text for assertive tone.
- func ele_debug_dump is updated, to remove constructing the format string.
- removed the macro usage for SOC_ID_MASK.
- used low case hex number.
- Condition will never occur, where msg_len satisfy the following condition "msg_len % 4 != 0". Err msg is added if it occurs.
- Function description is added to se_add_msg_crc.
- timeout is added to function ele_msg_rcv, in 5/5 patch.
- local variable "header" is initialized with "tx_msg" and replaced "return err" with "return tx_msg_sz" in func ele_msg_send().
- replace function name from "exception_for_size" to "check_hdr_exception_for_sz"
- replaced "return ret > 0 ? 0 : -1;" with "return ret > 0 ? 0 : ret;" in func "se_save_imem_state".
- func "se_restore_imem_state", to return if the condition is false to proceed.
- removed casting by (void *).
- removed devm_kasprintf and done direct allocatiion for attr->soc_id = "i.MX8ULP" & attr->soc_id = "i.MX8ULP", & attr->family.
- Followed Reverse christmas tree order, whereever missing.
- There is no return if ele_fw_authenticate fails. Execution flow continue forward and execute the fucn dma_free_coherent().
- The loop is not for retry. The loop is needed to load secondary fw followed by loading primary fw, first. This is the case when ELE also got reset.
- dev_err_probe is corrected in func "se_if_request_channel".
3/6
-
Reference:
- Link to v13: https://lore.kernel.org/r/20250311-imx-se-if-v13-0-9cc6d8fd6d1c@nxp.com
Changes in v13:
5/5
- Updated the commit message for imperative mood.
- Remove the usage of macros- NODE_NAME, GET_ASCII_TO_U8, GET_IDX_FROM_DEV_NODE_NAME.
- Clean-up the return path by replacing "ret = -<err>; return ret;" with "return -<err>;"
- Clean-up the return path by replacing "ret = -<err>; goto exit;" with "return -<err>;"
- Removed goto statements from the entire driver, where there is no common code at function's exit.
- Fixes the check-patch erros reported with flag "--strict"
- Replaced devm_add_action, with devm_add_action_or_reset
- Removed the un-necesary and obvious code comments.
- Removed dev_probe_err at the exit of function se_if_probe().
4/5
- Clean-up the return path by replacing "ret = -<err>; return ret;" with "return -<err>;"
- Clean-up the return path by replacing "ret = -<err>; goto exit;" with "return -<err>;"
- Removed goto statements from the entire driver, where there is no common code at function's exit.
- fixes the check-patch erros reported with flag "--strict"
- removed the un-necesary and obvious code comments.
- variable received msg timeout to be different at boot-up & suspend/resume and send/recv ioctlis.
3/5
- compatible string is modified from "fsl,imx8ulp-se" to "fsl,imx8ulp-se-ele-hsm".
- updated the alias name.
2/5
- compatible string is modified from "fsl,imx8ulp-se" to "fsl,imx8ulp-se-ele-hsm".
- compatible string is modified from "fsl,imx93-se" to "fsl,imx93-se-ele-hsm".
- compatible string is modified from "fsl,imx95-se" to "fsl,imx95-se-ele-hsm".
- Mis-understood the +1 from Conor. Hence dropped the Reviewed-by tag.
- Collected Rob's R-b tag on v7 (https://lore.kernel.org/all/172589152997.4184616.5889493628960272898.robh@kernel.org/)
1/5
- No change
Reference:
- Link to v12: https://lore.kernel.org/r/20250120-imx-se-if-v12-0-c5ec9754570c@nxp.com
Changes in v12:
5/5
- increased the wait-timeout.
4/5
- rename flag "handle_susp_resm" to "imem_mgmt"
- moved the buffer allocation ot load_fw->imem.buf, to se_probe_if.
- setting imem state at initialization.
3/5
- No change
2/5
- No change
1/5
- No change
Reference:
- Link to v11: https://lore.kernel.org/r/20241220-imx-se-if-v11-0-0c7e65d7ae7b@nxp.com
Changes in v11:
5/5
- devname is constructed by concatinating get_se_if_name(se_if_id) & se_if_instance_id.
- ele_rcv_msg(), is updated to add the wait_interruptible_timeout for the non-NVM-Daemon message exchanges, such that in case of no response from FW,
Linux donot hangs.
- added a new helper function get_se_if_name(), to return the secure-enclave interface owner's name string.
- added a new helper function get_se_soc_id(), to return the secure-enclave's SoC id.
4/5
- moved the se_if_node_info member "soc_register", to the struct "se_if_node_info_list"; as soc registration done once, not per interface.
- moved the se_if_node_info member "se_fetch_soc_info", to the struct "se_if_node_info_list"; as soc info fetching is done once, not per interface.
- Added two member variable se_if_id and se_if_instance_id to struct se_if_defines.
- removed the member "se_name" from struct "se_if_node_info". Rather, it will constructed by concatinating get_se_if_name(se_if_id) & se_if_instance_id.
- moved the static global variable "se_version", to the newly created structure "struct se_var_info".
- moved the member "struct se_fw_load_info load_fw" of "se_if_node_info_list", to the newly created structure "struct se_var_info".
- Replaced RUNTIME_PM_OPS with SET_SYSTEM_SLEEP_PM_OPS, in power-managment ops.
3/5
- No change
2/5
- No change
1/5
- No change
Reference:
- Link to v10: https://lore.kernel.org/r/20241104-imx-se-if-v10-0-bf06083cc97f@nxp.com
v10: firmware: imx: driver for NXP secure-enclave
Changes in v10:
5/5
- replaced the u8, u16, u32, u64, with __u8, __u16, __u32, __u64 in
'include/uapi/linux/se_ioctl.h'.
4/5
- No change
3/5
- No change
2/5
- No change
1/5
- No change
Reference:
- Link to v9: https://lore.kernel.org/r/20241016-imx-se-if-v9-0-fd8fa0c04eab@nxp.com
Changes in v9:
4/5
- change se_if_remove function signature, required after rebase to v6.12-rc1.
- move the info->macros to a structure "struct se_if_defines if_defs".
- Removed "info" from "struct se_if_defines if_defs".
- Moved "mem_pool" from "struct se_if_defines if_defs" to "priv".
- Fetching "info" using container-of.
5/5
- Fetching "info" using container-of.
- Fixed issue reported by sparse.
Reference:
- Link to v8: https://lore.kernel.org/r/20241015-imx-se-if-v8-0-915438e267d3@nxp.com
Changes in v8:
5/5
- Remove the check for SE_IF_CTX_OPENED.
- replaced dev_ctx->priv-dev, priv->dev, whereever possible.
- func "if_misc_deregister" moved before func "init_device_context".
- func "init_device_context" before func "se_ioctl_cmd_snd_rcv_rsp_handler".
- func "se_if_fops_write" and "se_if_fops_read", are moved after func "se_ioctl_get_mu_info".
- non static functions "se_dev_ctx_cpy_out_data, se_dev_ctx_shared_mem_cleanup & init_device_context" are moved static and local scope.
- Removed back & forth between the two structs "struct se_if_device_ctx *dev_ctx" and "struct se_shared_mem_mgmt_info *se_shared_mem_mgmt"
- removed the NULL check for bdesc.
- fops_open, is corrected for acquiring the fops_lock.
- Fops_close, mutex unlock is removed. Infact check for waiting_rsp_clbk_hdl.dev_ctx, is removed.
- sema_init(&dev_ctx->fops_lock, 1);, replaced with Mutex.
- structure member se_notify, is removed.
4/5
- removed initializing err to zero in func ele_fetch_soc_info(),
- replaced 'return 0', with 'goto exit', if the condition (!priv->mem_pool) is true.
- replaced "struct *dev" with "struct se_if_priv *priv", in base_message API(s) and others.
- Created a separate structure "struct se_if_defines" to maintain interface's fixed values like cmd_tag, rsp_tag, success_tag etc.
- removed the macros "WORD_SZ", "SOC_VER_MASK", "DEFAULT_IMX_SOC_VER", "RESERVED_DMA_POOL".
- Added handling for "ctrl+c", by postponing the interrupt, till the response to the "command in flight" is received.
- Removed the mutext lock "se_if_lock".
- furnction prototype for "se_save_imem_state" and "se_restore_imem_state", is changed to pass "imem" by reference.
- Added a new structure "struct se_fw_load_info", dedicated to contain FW loading relevant info. It is a member of struct info_list.
- split "imem_mgmt_file_in_rfs" into two "prim_fw_nm_in_rfs" and "seco_fw_nm_in_rfs", to be part of "struct se_fw_load_info".
- moved the function "se_load_firmware" prior to func "if_mbox_free_channel".
- function "se_load_firmware" is updated to use "request_firmware", instead of "request_firmware_no_wait".
- function "se_load_firmware" is updated to load "primary" fw image, if the imem_state is not BAD. Then load the "secondary FW" image.
- Added a new mutex_lock in the function "se_load_firmware", for ensuring FW loading done once, when there are multiple application are in play.
- instead of "wait_queue_head_t wq", used "sruct completion".
- add devm_add_action with action as se_if_probe_cleanup.
Reference:
- Link to v7: https://lore.kernel.org/r/20240904-imx-se-if-v7-0-5afd2ab74264@nxp.com
Changes in v7:
5/5
- struct se_clbk_handle, is added with a member struct se_if_device_ctx *dev_ctx.
- func call to ele_miscdev_msg_rcv() & ele_miscdev_msg_send(), are removed.
- func se_ioctl_cmd_snd_rcv_rsp_handler(), is modified to remove the func call to ele_miscdev_msg_rcv() & ele_miscdev_msg_send()
- func se_ioctl_cmd_snd_rcv_rsp_handler is callig func ele_msg_send_rcv(), instead.
- Mutext "se_cmd_if_lock", handling is removed from this patch.
- func ele_miscdev_msg_send() is replaced with func ele_msg_send(), in fops_write.
- func ele_miscdev_msg_rcv() is replaced with func ele_msg_rcv(), in fops_read.
- fops_open is modified to create the new dev_ctx instance (using func init_device_context()), which is not registered as miscdev.
- Only one dev_ctx is registered as miscdev and its reference is stored in the struct se_if_priv, as priv_dev_ctx.
- Separate func cleanup_se_shared_mem() & func init_se_shared_mem(), for shared memory handling part of struct dev_ctx.
- Input param for func(s) ele_msg_rcv(), ele_msg_send() & ele_msg_send_rcv(), is replaced from struct se_if_priv to struct se_if_device_ctx.
4/5
- A new structure is defined name struct "se_clbk_handle", to contain members processed in mailbox call-back function.
- "struct se_if_priv" is modified to contain the two structures of "se_clbk_handle" - waiting_rsp_clbk_hdl & cmd_receiver_clbk_hdl.
- func ele_msg_rcv() is modified to take a new additional input reference param "struct se_clbk_handle *se_clbk_hdl".
- func ele_msg_send() is modified to take a new additional input tx_msg_sz.
- func ele_msg_send_rcv(), is modified to take 2 more inputs - tx_msg_sz & exp_rx_msg_sz.
- func se_val_rsp_hdr_n_status(), is modified to take input of rx_msg buffer, instead of header value, as input param.
- each caller of the func ele_msg_send_rcv(), is sending these two additional input params.
- func se_if_callback(), is modified to work on two structures of "se_clbk_handle" - waiting_rsp_clbk_hdl & cmd_receiver_clbk_hdl.
- Variable "max_dev_ctx", is removed from info & priv struture, as well its usage.
- New member variable "se_img_file_to_load", is added to structure "priv".
- Other member variables - rx_msg(ptr), rx_msg_sz, completion done & list of dev_ctxs, is removed from priv struture, along with their usage.
- func se_resume(), updated to wakeup the two "wq", part of "struct se_clbk_handle": priv->waiting_rsp_clbk_hdl & priv->cmd_receiver_clbk_hdl.
3/5
- Node name is changed from senclave-firmware@0 to "secure-enclave"
2/5
- Node name is changed to "secure-enclave".
Reference:
- Link to v6: https://lore.kernel.org/r/20240722-imx-se-if-v6-0-ee26a87b824a@nxp.com
Changes in v6:
5/5
- replaced scope_gaurd with gaurd.
4/5
- replaced scope_gaurd with gaurd.
- remove reading the regs property from dtb.
- Added NULL check for priv data fetched from device, as a sanity check, for ele_base_msg apis)
3/5
- replace firmware with senclave-firmware.
2/5
- replace firmware with senclave-firmware.
- drop description for mbox
- Replaced "items:" with maxItems:1 for "memory-region"
- Replaced "items:" with maxItems:1 for "sram"
- remove regs property.
- remove "$nodename"
Reference:
- Link to v5: https://lore.kernel.org/r/20240712-imx-se-if-v5-0-66a79903a872@nxp.com
Changes in v5:
2/5
- updated the description of mboxes
- updated the description & items for mbox-names.
- updated the description of memory-region
- move "additional properties: false" after allOf block.
- removed other example except one.
4/5
- Corrected the indentation in Kconfig.
- info members:mbox_tx_name & mbox_rx_name, are replaced with macros.
5/5
- Replaced "for secure enclaves", with "for secure enclaves"
- Replaced "user space" with "userspace".
- End the line "[include]<linux/firmware/imx/ele_mu_ioctl.h>" with a period.
Reference:
- Link to v4: https://lore.kernel.org/r/20240705-imx-se-if-v4-0-52d000e18a1d@nxp.com
Changes in v4:
1/5
a. Removed - from EdgeLock Enclave.
b. Removed , after "Each of the above feature,"
c. replace "can exists" with "can exist".
d.
-messaging units(MU) per SE. Each co-existing 'se' can have one or multiple exclusive
-MU(s), dedicated to itself. None of the MU is shared between two SEs.
+messaging units(MU) per SE. Each co-existing SE can have one or multiple exclusive
+MUs, dedicated to itself. None of the MU is shared between two SEs.
Communication of the MU is realized using the Linux mailbox driver.
e.
-All those SE interfaces 'se-if' that is/are dedicated to a particular SE, will be
-enumerated and provisioned under the very single 'SE' node.
+Although MU(s) is/are not shared between SE(s). But for SoC like i.MX95 which has
+multiple SE(s) like HSM, V2X-HSM, V2X-SHE; all the SE(s) and their interfaces 'se-if'
+that is/are dedicated to a particular SE will be enumerated and provisioned using the
+single compatible node("fsl,imx95-se").
f. Removed ",". Replaced for "Each 'se-if'," with "Each se-if'.
g. removed ","
- This layer is responsible for ensuring the communication protocol, that is defined
+ This layer is responsible for ensuring the communication protocol that is defined
h. removed "-"
- - FW can handle one command-message at a time.
+ - FW can handle one command message at a time.
i.
- Using these multiple device contexts, that are getting multiplexed over a single MU,
- user-space application(s) can call fops like write/read to send the command-message,
- and read back the command-response-message to/from Firmware.
- fops like read & write uses the above defined service layer API(s) to communicate with
+ Using these multiple device contexts that are getting multiplexed over a single MU,
+ userspace application(s) can call fops like write/read to send the command message,
+ and read back the command response message to/from Firmware.
+ fops like read & write use the above defined service layer API(s) to communicate with
Firmware.
j. Uppercase for word "Linux".
2/5
a. Rephrased the description to remove list of phandles.
b. Moved required before allOf:
+required:
+ - compatible
+ - reg
+ - mboxes
+ - mbox-names
+
+additionalProperties: false
+
allOf:
c. replaced not: required: with properties: <property-name>: false.
# memory-region
- not:
- required:
- - memory-region
+ properties:
+ memory-region: false
# sram
- else:
- not:
- required:
- - sram
d. Reduced examples. keeping example of i.MX95.
e. node-name is changed to "firmware@<hex>"
3/5
- node name changed to "firmware@<hex>".
4/5
- used sizeof(*s_info)
- return early, rather than doing goto exit, in ele_get_info().
- Use upper_32_bits() and lower_32_bits()
- use rx_msg here instead of priv->rx_msg
- Moved the status check to validate_rsp_hdr. Rename the function to "se_val_rsp_hdr_n_status"
- typecasting removed header = (struct se_msg_hdr *) msg;
- Converted the API name with prefix imx_ele_* or imx_se_*, to ele_* and se_*, respectively.
- Removed the functions definition & declaration for: free_phybuf_mem_pool() & get_phybuf_mem_pool()
- removed the mbox_free_channel() calls from clean-up.
- Flag "priv->flags" is removed.
- Converted the int se_if_probe_cleanup() to void se_if_probe_cleanup().
- Replaced NULL initialization of structure members: priv->cmd_receiver_dev & priv->waiting_rsp_dev , with comments.
- Removed the function's declaration get_phy_buf_mem_pool1
5/5
Changes to Documentation/ABI/testing/se-cdev.
a. Removed "-" from "secure-enclave" and "file-descriptor".
b. Removed "-" from "shared-library"
c. Replaced "get" with "getting".
d. Added description for the new IOCTL "send command and receive command response"
e. Replaced "wakeup_intruptible" with "wait_event_interruptible"
f. Removed ";"
g. Removd "," from "mailbox_lock,"
h. Replaced "free" with "frees"
i. In mailbox callback function, checking the buffer size before
copying.
Reference:
- Link to v3: https://lore.kernel.org/r/20240617-imx-se-if-v3-0-a7d28dea5c4a@nxp.com
Changes in v3:
5/5:
- Initialize tx_msg with NULL.
- memdup_user() returns an error pointer, not NULL. correct it by adding check for err_ptr.
- new IOCTL is added to send & recieve the message.
- replaced the while loop till list is empty, with list_for_each_entry.
- replaced __list_del_entry, with list_del.
- Removed the dev_err message from copy to user.
- Removed the casting of void *.
- corrected the typcasting in copy to user.
- removed un-necessary goto statement.
- Removed dead code for clean-up of memory.
- Removed un-mapping of secured memory
- Passing se_if_priv structure to init_device_context.
- Updated the below check to replace io.length with round_up(io.length).
if (shared_mem->size < shared_mem->pos|| io.length >= shared_mem->size - shared_mem->pos)
- Created a function to cleanup the list of shared memory buffers.
- Used list_for_each_entry_safe(). created a separate functions: se_dev_ctx_cpy_out_data() & se_dev_ctx_shared_mem_cleanup()
4/5
- Changed the compatible string to replace "-ele", to "-se".
- Declaration of imx_se_node_info, is done as const in the whole file
- Remove the unused macros from ele_base_msg.h
- Remove the function declaration get_phy_buf_mem_pool1, from the header file.
- Replace the use of dmam_alloc_coherent to dma_alloc_coherent
- Check for function pointer, before calling the fucntion pointer in imx_fetch_se_soc_info
- Removed the unused flag for SE_MU_IO_FLAGS_USE_SEC_MEM.
- Removed the unused macros WORD_SZ
- instead of struct device *dev, struct se_if_priv *priv, is used as argument to the funtions:se_save_imem_state, se_restore_imem_state, imx_fetch_se_soc_info
- Removed ret from validate_rsp_hdr.
- changed the prefix of the funtion: plat_add_msg_crc and plat_fill_cmd_msg_hdr.
- indentation correction for info structures.
- remove the check for priv not null from se_if_probe_cleanup
- Removed the casting of void *.
- se_load_firmware function is corrected for not freeing the buffer when allocation fails.
- Checking if get_imx_se_node_info() can return NULL, in se_if_probe()
- imem.size has type u32. return value from se_save_imem_state() will be assigned to imem.size in case of success only.
- removed the flag un-setting in case of failure. priv->flags &= (~RESERVED_DMA_POOL);
- removed the function call for devm_of_platform_populate(dev);
- Checking for not-NULL, before calling the funtion pointer se_fetch_soc_info.
- Removed the checking for reserved memory flag, before freeing up the reserved memory, in se_probe_if_cleanup.
3/5
- Changed the compatible string to replace "-ele", to "-se".
2/5
- to fix the warning error, replaced the "-ele" & "-v2x" in compatible string, to "-se".
- Added an example for ele@0 for compatible string "fsl,imx95-se"
Reference
- Link to v2: https://lore.kernel.org/r/20240523-imx-se-if-v2-0-5a6fd189a539@nxp.com
Changes in v2:
4/4
- Split this patch into two: 1. base driver & 2. Miscdev
- Initialize the return variable "err" as 0, before calling 'return err', in the file ele_common.c
- Fix the usage of un-iniitialized pointer variable, by initializing them with NULL, in ele_base_msg.c.
- Fix initializing the ret variable, to return the correct error code in case of issue.
- replaced dmam_alloc_coherent with dma_alloc_coherent.
- Replace the use of ELE_GET_INFO_READ_SZ, with sizeof(soc_info).
- Replaced -1 with -EPERM
- Removed the safety check on func-input param, in ele_get_info().
- fix the assigning data[1] with lower 32 address, rather than zero, for ele_fw_authenticate API.
- Correctly initializing the function's return error code, for file ele_base_msg.c.
- replaced 'return' with 'goto'.
- Use length in bytes.
- Corrected the structure se_msg_hdr.
- Moved setting of rx_msg to priv, into the function imx_ele_msg_send_rcv
- Will add lockdep_assert_held, to receive path, in v2.
- corrected the spacing at "ret = validate_rsp_hdr"
- FIELD_GET() used for RES_STATUS
- Re-write the structure soc_info, matching the information provided in response to this api.
- The "|" goes to the end of the previous line.
- Moved the locking and unlocking of the command lock to the caller of the function.
- removed the safety check for device private data.
- Structure memory reference, used to read message header.
- In the interrupt call back function, remove assigning waiting_rsp_dev to NULL, in case of response message rcv from FW.
- do while removed.
- replaced BIT(1) for RESERVED_DMA_POOL, to BIT(0)
- The backslash is removed while assigning the file name with absolute path to structure variable.fw_name_in_rfs =.
- Update the 'if' condition by removing "idx < 0".
- mbox_request_channel_byname() uses a "char" for the name not a u8. Corrected.
- devm managed resources, are not cleaned now, in function se_probe_if_cleanup
- Used dev_err_probe().
- Used %pe to print error string.
- remove "__maybe_unused" for "struct platform_device *enum_plat_dev __maybe_unused;"
- used FIELD_GET(), for RES_STATUS. Removed the use of MSG_TAG, MSG_COMMAND, MSG_SIZE, MSG_VER.
- Depricated the used of member of struct se_if_priv, bool no_dev_ctx_used;
- Moved the text explaing the synchronization logic via mutexes, from patch 1/4 to se_ctrl.h.
- removed the type casting of info_list = (struct imx_se_node_info_list *) device_get_match_data(dev->parent);
- Used static variable priv->soc_rev in the se_ctrl.c, replaced the following condition: if (info_list->soc_rev) to if (priv->soc_rev) for checking if this flow is already executed or not.
- imx_fetch_soc_info will return failure if the get_info function fails.
- Removed devm_free from imx_fetch_soc_info too.
3/3
- Made changes to move all the properties to parent node, without any child node.
2/4
- Use Hex pattern string.
- Move the properties to parent node, with no child node.
- Add i.MX95-ele to compatible nodes to fix the warning "/example-2/v2x: failed to match any schema with compatible: ['fsl,imx95-v2x']"
1/1
- Corrected the spelling from creats to creates.
- drop the braces around the plural 's' for interfaces
- written se in upper case SE.
- Replace "multiple message(s)" with messages.
- Removed too much details about locks.
Testing
- make CHECK_DTBS=y freescale/imx8ulp-evk.dtb;
- make ARCH=arm64 CROSS_COMPILE=aarch64-linux-gnu- -j8 dt_binding_check DT_SCHEMA_FILES=fsl,imx-se.yaml
- make C=1 CHECK=scripts/coccicheck drivers/firmware/imx/*.* W=1 > r.txt
- ./scripts/checkpatch.pl --git <>..HEAD
- Tested the Image and .dtb, on the i.MX8ULP.
Reference
- Link to v1: https://lore.kernel.org/r/20240510-imx-se-if-v1-0-27c5a674916d@nxp.com
---
Pankaj Gupta (7):
Documentation/firmware: add imx/se to other_interfaces
dt-bindings: arm: fsl: add imx-se-fw binding doc
firmware: imx: add driver for NXP EdgeLock Enclave
firmware: imx: device context dedicated to priv
firmware: drivers: imx: adds miscdev
arm64: dts: imx8ulp: add secure enclave node
arm64: dts: imx8ulp-evk: add reserved memory property
Documentation/ABI/testing/se-cdev | 44 +
.../devicetree/bindings/firmware/fsl,imx-se.yaml | 91 ++
.../driver-api/firmware/other_interfaces.rst | 133 ++
arch/arm64/boot/dts/freescale/imx8ulp-evk.dts | 12 +-
arch/arm64/boot/dts/freescale/imx8ulp.dtsi | 11 +-
drivers/firmware/imx/Kconfig | 13 +
drivers/firmware/imx/Makefile | 2 +
drivers/firmware/imx/ele_base_msg.c | 305 +++++
drivers/firmware/imx/ele_base_msg.h | 117 ++
drivers/firmware/imx/ele_common.c | 478 +++++++
drivers/firmware/imx/ele_common.h | 51 +
drivers/firmware/imx/se_ctrl.c | 1441 ++++++++++++++++++++
drivers/firmware/imx/se_ctrl.h | 159 +++
include/linux/firmware/imx/se_api.h | 14 +
include/uapi/linux/se_ioctl.h | 97 ++
15 files changed, 2965 insertions(+), 3 deletions(-)
---
base-commit: dc59e4fea9d83f03bad6bddf3fa2e52491777482
change-id: 20240507-imx-se-if-a40055093dc6
Best regards,
--
Pankaj Gupta <pankaj.gupta@nxp.com>
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