* Re: [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 20:32 [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper Jiri Olsa
@ 2022-09-27 20:41 ` Liang, Kan
2022-09-27 20:46 ` Peter Zijlstra
` (2 subsequent siblings)
3 siblings, 0 replies; 7+ messages in thread
From: Liang, Kan @ 2022-09-27 20:41 UTC (permalink / raw)
To: Jiri Olsa, Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo
Cc: lkml, Ingo Molnar, Alexander Shishkin, Mark Rutland, Namhyung Kim,
bpf, Song Liu, Daniel Xu
On 2022-09-27 4:32 p.m., Jiri Olsa wrote:
> Recent commit [1] changed branch stack data indication from
> br_stack pointer to sample_flags in perf_sample_data struct.
>
> We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
> bit for valid branch stack data.
>
> [1] a9a931e26668 ("perf: Use sample_flags for branch stack")
>
> Cc: Kan Liang <kan.liang@linux.intel.com>
> Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Thanks for the fix.
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Thanks,
Kan
> ---
> NOTE sending on top of tip/master because [1] is not
> merged in bpf-next/master yet
>
> kernel/trace/bpf_trace.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index 68e5cdd24cef..1fcd1234607e 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -1507,6 +1507,9 @@ BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
> if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
> return -EINVAL;
>
> + if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
> + return -ENOENT;
> +
> if (unlikely(!br_stack))
> return -ENOENT;
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 20:32 [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper Jiri Olsa
2022-09-27 20:41 ` Liang, Kan
@ 2022-09-27 20:46 ` Peter Zijlstra
2022-09-27 21:24 ` Jiri Olsa
2022-09-27 21:49 ` Song Liu
2022-09-28 6:57 ` [tip: perf/core] " tip-bot2 for Jiri Olsa
3 siblings, 1 reply; 7+ messages in thread
From: Peter Zijlstra @ 2022-09-27 20:46 UTC (permalink / raw)
To: Jiri Olsa
Cc: Ingo Molnar, Arnaldo Carvalho de Melo, Kan Liang, lkml,
Ingo Molnar, Alexander Shishkin, Mark Rutland, Namhyung Kim, bpf,
Song Liu, Daniel Xu
On Tue, Sep 27, 2022 at 10:32:59PM +0200, Jiri Olsa wrote:
> Recent commit [1] changed branch stack data indication from
> br_stack pointer to sample_flags in perf_sample_data struct.
>
> We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
> bit for valid branch stack data.
>
> [1] a9a931e26668 ("perf: Use sample_flags for branch stack")
>
> Cc: Kan Liang <kan.liang@linux.intel.com>
> Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> ---
> NOTE sending on top of tip/master because [1] is not
> merged in bpf-next/master yet
Shall I stick this in tip/perf/core right along with [1] then?
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 20:46 ` Peter Zijlstra
@ 2022-09-27 21:24 ` Jiri Olsa
0 siblings, 0 replies; 7+ messages in thread
From: Jiri Olsa @ 2022-09-27 21:24 UTC (permalink / raw)
To: Peter Zijlstra
Cc: Ingo Molnar, Arnaldo Carvalho de Melo, Kan Liang, lkml,
Ingo Molnar, Alexander Shishkin, Mark Rutland, Namhyung Kim, bpf,
Song Liu, Daniel Xu
On Tue, Sep 27, 2022 at 10:46:12PM +0200, Peter Zijlstra wrote:
> On Tue, Sep 27, 2022 at 10:32:59PM +0200, Jiri Olsa wrote:
> > Recent commit [1] changed branch stack data indication from
> > br_stack pointer to sample_flags in perf_sample_data struct.
> >
> > We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
> > bit for valid branch stack data.
> >
> > [1] a9a931e26668 ("perf: Use sample_flags for branch stack")
> >
> > Cc: Kan Liang <kan.liang@linux.intel.com>
> > Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
> > Signed-off-by: Jiri Olsa <jolsa@kernel.org>
> > ---
> > NOTE sending on top of tip/master because [1] is not
> > merged in bpf-next/master yet
>
> Shall I stick this in tip/perf/core right along with [1] then?
yes, sounds good
thanks,
jirka
^ permalink raw reply [flat|nested] 7+ messages in thread
* Re: [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 20:32 [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper Jiri Olsa
2022-09-27 20:41 ` Liang, Kan
2022-09-27 20:46 ` Peter Zijlstra
@ 2022-09-27 21:49 ` Song Liu
2022-09-27 21:50 ` Song Liu
2022-09-28 6:57 ` [tip: perf/core] " tip-bot2 for Jiri Olsa
3 siblings, 1 reply; 7+ messages in thread
From: Song Liu @ 2022-09-27 21:49 UTC (permalink / raw)
To: Jiri Olsa
Cc: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Kan Liang,
lkml, Ingo Molnar, Alexander Shishkin, Mark Rutland, Namhyung Kim,
bpf@vger.kernel.org, Daniel Xu
> On Sep 27, 2022, at 1:32 PM, Jiri Olsa <jolsa@kernel.org> wrote:
>
> Recent commit [1] changed branch stack data indication from
> br_stack pointer to sample_flags in perf_sample_data struct.
>
> We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
> bit for valid branch stack data.
>
> [1] a9a931e26668 ("perf: Use sample_flags for branch stack")
>
> Cc: Kan Liang <kan.liang@linux.intel.com>
> Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Thanks for the fix! I noticed the issue last week, but haven't
got time to look into it.
Song
> ---
> NOTE sending on top of tip/master because [1] is not
> merged in bpf-next/master yet
>
> kernel/trace/bpf_trace.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
> index 68e5cdd24cef..1fcd1234607e 100644
> --- a/kernel/trace/bpf_trace.c
> +++ b/kernel/trace/bpf_trace.c
> @@ -1507,6 +1507,9 @@ BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
> if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
> return -EINVAL;
>
> + if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
> + return -ENOENT;
> +
> if (unlikely(!br_stack))
> return -ENOENT;
>
> --
> 2.37.3
>
^ permalink raw reply [flat|nested] 7+ messages in thread* Re: [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 21:49 ` Song Liu
@ 2022-09-27 21:50 ` Song Liu
0 siblings, 0 replies; 7+ messages in thread
From: Song Liu @ 2022-09-27 21:50 UTC (permalink / raw)
To: Jiri Olsa
Cc: Peter Zijlstra, Ingo Molnar, Arnaldo Carvalho de Melo, Kan Liang,
lkml, Ingo Molnar, Alexander Shishkin, Mark Rutland, Namhyung Kim,
bpf@vger.kernel.org, Daniel Xu
> On Sep 27, 2022, at 2:49 PM, Song Liu <songliubraving@fb.com> wrote:
>
>
>
>> On Sep 27, 2022, at 1:32 PM, Jiri Olsa <jolsa@kernel.org> wrote:
>>
>> Recent commit [1] changed branch stack data indication from
>> br_stack pointer to sample_flags in perf_sample_data struct.
>>
>> We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
>> bit for valid branch stack data.
>>
>> [1] a9a931e26668 ("perf: Use sample_flags for branch stack")
>>
>> Cc: Kan Liang <kan.liang@linux.intel.com>
>> Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
>> Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
>
> Thanks for the fix! I noticed the issue last week, but haven't
> got time to look into it.
>
> Song
>
>> ---
>> NOTE sending on top of tip/master because [1] is not
>> merged in bpf-next/master yet
>>
>> kernel/trace/bpf_trace.c | 3 +++
>> 1 file changed, 3 insertions(+)
>>
>> diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
>> index 68e5cdd24cef..1fcd1234607e 100644
>> --- a/kernel/trace/bpf_trace.c
>> +++ b/kernel/trace/bpf_trace.c
>> @@ -1507,6 +1507,9 @@ BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
>> if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
>> return -EINVAL;
>>
>> + if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
>> + return -ENOENT;
>> +
>> if (unlikely(!br_stack))
>> return -ENOENT;
>>
>> --
>> 2.37.3
^ permalink raw reply [flat|nested] 7+ messages in thread
* [tip: perf/core] bpf: Check flags for branch stack in bpf_read_branch_records helper
2022-09-27 20:32 [PATCH -tip] bpf: Check flags for branch stack in bpf_read_branch_records helper Jiri Olsa
` (2 preceding siblings ...)
2022-09-27 21:49 ` Song Liu
@ 2022-09-28 6:57 ` tip-bot2 for Jiri Olsa
3 siblings, 0 replies; 7+ messages in thread
From: tip-bot2 for Jiri Olsa @ 2022-09-28 6:57 UTC (permalink / raw)
To: linux-tip-commits
Cc: Jiri Olsa, Peter Zijlstra (Intel), Kan Liang, x86, linux-kernel
The following commit has been merged into the perf/core branch of tip:
Commit-ID: cce6a2d7e0e494c453ad73e1e78bd50684f20cca
Gitweb: https://git.kernel.org/tip/cce6a2d7e0e494c453ad73e1e78bd50684f20cca
Author: Jiri Olsa <jolsa@kernel.org>
AuthorDate: Tue, 27 Sep 2022 22:32:59 +02:00
Committer: Peter Zijlstra <peterz@infradead.org>
CommitterDate: Tue, 27 Sep 2022 22:50:25 +02:00
bpf: Check flags for branch stack in bpf_read_branch_records helper
Recent commit [1] changed branch stack data indication from
br_stack pointer to sample_flags in perf_sample_data struct.
We need to check sample_flags for PERF_SAMPLE_BRANCH_STACK
bit for valid branch stack data.
[1] a9a931e26668 ("perf: Use sample_flags for branch stack")
Fixes: a9a931e26668 ("perf: Use sample_flags for branch stack")
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Link: https://lore.kernel.org/r/20220927203259.590950-1-jolsa@kernel.org
---
kernel/trace/bpf_trace.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c
index 68e5cdd..1fcd123 100644
--- a/kernel/trace/bpf_trace.c
+++ b/kernel/trace/bpf_trace.c
@@ -1507,6 +1507,9 @@ BPF_CALL_4(bpf_read_branch_records, struct bpf_perf_event_data_kern *, ctx,
if (unlikely(flags & ~BPF_F_GET_BRANCH_RECORDS_SIZE))
return -EINVAL;
+ if (unlikely(!(ctx->data->sample_flags & PERF_SAMPLE_BRANCH_STACK)))
+ return -ENOENT;
+
if (unlikely(!br_stack))
return -ENOENT;
^ permalink raw reply related [flat|nested] 7+ messages in thread