linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] perf stat: Fix segfault on armv8_pmu events
@ 2020-10-07  8:13 Namhyung Kim
  2020-10-07 11:42 ` Jiri Olsa
  0 siblings, 1 reply; 3+ messages in thread
From: Namhyung Kim @ 2020-10-07  8:13 UTC (permalink / raw)
  To: Arnaldo Carvalho de Melo, Jiri Olsa
  Cc: Ingo Molnar, Peter Zijlstra, Mark Rutland, Alexander Shishkin,
	LKML, Stephane Eranian, Wei Li, Barry Song

It was reported that perf stat crashed when using with armv8_pmu (cpu)
events with the task mode.  As perf stat uses an empty cpu map for
task mode but armv8_pmu has its own cpu mask, it confused which map
should use when accessing file descriptors and caused segfaults:

  (gdb) bt
  #0  0x0000000000603fc8 in perf_evsel__close_fd_cpu (evsel=<optimized out>,
      cpu=<optimized out>) at evsel.c:122
  #1  perf_evsel__close_cpu (evsel=evsel@entry=0x716e950, cpu=7) at evsel.c:156
  #2  0x00000000004d4718 in evlist__close (evlist=0x70a7cb0) at util/evlist.c:1242
  #3  0x0000000000453404 in __run_perf_stat (argc=3, argc@entry=1, argv=0x30,
      argv@entry=0xfffffaea2f90, run_idx=119, run_idx@entry=1701998435)
      at builtin-stat.c:929
  #4  0x0000000000455058 in run_perf_stat (run_idx=1701998435, argv=0xfffffaea2f90,
      argc=1) at builtin-stat.c:947
  #5  cmd_stat (argc=1, argv=0xfffffaea2f90) at builtin-stat.c:2357
  #6  0x00000000004bb888 in run_builtin (p=p@entry=0x9764b8 <commands+288>,
      argc=argc@entry=4, argv=argv@entry=0xfffffaea2f90) at perf.c:312
  #7  0x00000000004bbb54 in handle_internal_command (argc=argc@entry=4,
      argv=argv@entry=0xfffffaea2f90) at perf.c:364
  #8  0x0000000000435378 in run_argv (argcp=<synthetic pointer>,
      argv=<synthetic pointer>) at perf.c:408
  #9  main (argc=4, argv=0xfffffaea2f90) at perf.c:538

To fix this, I simply used the given cpu map unless the evsel actually
is not a system-wide event (like uncore events).

Reported-by: Wei Li <liwei391@huawei.com>
Tested-by: Barry Song <song.bao.hua@hisilicon.com>
Fixes: 7736627b865d ("perf stat: Use affinity for closing file descriptors")
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
---
 tools/lib/perf/evlist.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
index 2208444ecb44..cfcdbd7be066 100644
--- a/tools/lib/perf/evlist.c
+++ b/tools/lib/perf/evlist.c
@@ -45,6 +45,9 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
 	if (!evsel->own_cpus || evlist->has_user_cpus) {
 		perf_cpu_map__put(evsel->cpus);
 		evsel->cpus = perf_cpu_map__get(evlist->cpus);
+	} else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) {
+		perf_cpu_map__put(evsel->cpus);
+		evsel->cpus = perf_cpu_map__get(evlist->cpus);
 	} else if (evsel->cpus != evsel->own_cpus) {
 		perf_cpu_map__put(evsel->cpus);
 		evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
-- 
2.28.0.806.g8561365e88-goog


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* Re: [PATCH] perf stat: Fix segfault on armv8_pmu events
  2020-10-07  8:13 [PATCH] perf stat: Fix segfault on armv8_pmu events Namhyung Kim
@ 2020-10-07 11:42 ` Jiri Olsa
  2020-10-07 13:00   ` Arnaldo Carvalho de Melo
  0 siblings, 1 reply; 3+ messages in thread
From: Jiri Olsa @ 2020-10-07 11:42 UTC (permalink / raw)
  To: Namhyung Kim
  Cc: Arnaldo Carvalho de Melo, Ingo Molnar, Peter Zijlstra,
	Mark Rutland, Alexander Shishkin, LKML, Stephane Eranian, Wei Li,
	Barry Song

On Wed, Oct 07, 2020 at 05:13:11PM +0900, Namhyung Kim wrote:
> It was reported that perf stat crashed when using with armv8_pmu (cpu)
> events with the task mode.  As perf stat uses an empty cpu map for
> task mode but armv8_pmu has its own cpu mask, it confused which map
> should use when accessing file descriptors and caused segfaults:
> 
>   (gdb) bt
>   #0  0x0000000000603fc8 in perf_evsel__close_fd_cpu (evsel=<optimized out>,
>       cpu=<optimized out>) at evsel.c:122
>   #1  perf_evsel__close_cpu (evsel=evsel@entry=0x716e950, cpu=7) at evsel.c:156
>   #2  0x00000000004d4718 in evlist__close (evlist=0x70a7cb0) at util/evlist.c:1242
>   #3  0x0000000000453404 in __run_perf_stat (argc=3, argc@entry=1, argv=0x30,
>       argv@entry=0xfffffaea2f90, run_idx=119, run_idx@entry=1701998435)
>       at builtin-stat.c:929
>   #4  0x0000000000455058 in run_perf_stat (run_idx=1701998435, argv=0xfffffaea2f90,
>       argc=1) at builtin-stat.c:947
>   #5  cmd_stat (argc=1, argv=0xfffffaea2f90) at builtin-stat.c:2357
>   #6  0x00000000004bb888 in run_builtin (p=p@entry=0x9764b8 <commands+288>,
>       argc=argc@entry=4, argv=argv@entry=0xfffffaea2f90) at perf.c:312
>   #7  0x00000000004bbb54 in handle_internal_command (argc=argc@entry=4,
>       argv=argv@entry=0xfffffaea2f90) at perf.c:364
>   #8  0x0000000000435378 in run_argv (argcp=<synthetic pointer>,
>       argv=<synthetic pointer>) at perf.c:408
>   #9  main (argc=4, argv=0xfffffaea2f90) at perf.c:538
> 
> To fix this, I simply used the given cpu map unless the evsel actually
> is not a system-wide event (like uncore events).
> 
> Reported-by: Wei Li <liwei391@huawei.com>
> Tested-by: Barry Song <song.bao.hua@hisilicon.com>
> Fixes: 7736627b865d ("perf stat: Use affinity for closing file descriptors")
> Signed-off-by: Namhyung Kim <namhyung@kernel.org>

Acked-by: Jiri Olsa <jolsa@redhat.com>

thanks,
jirka

> ---
>  tools/lib/perf/evlist.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
> index 2208444ecb44..cfcdbd7be066 100644
> --- a/tools/lib/perf/evlist.c
> +++ b/tools/lib/perf/evlist.c
> @@ -45,6 +45,9 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
>  	if (!evsel->own_cpus || evlist->has_user_cpus) {
>  		perf_cpu_map__put(evsel->cpus);
>  		evsel->cpus = perf_cpu_map__get(evlist->cpus);
> +	} else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) {
> +		perf_cpu_map__put(evsel->cpus);
> +		evsel->cpus = perf_cpu_map__get(evlist->cpus);
>  	} else if (evsel->cpus != evsel->own_cpus) {
>  		perf_cpu_map__put(evsel->cpus);
>  		evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
> -- 
> 2.28.0.806.g8561365e88-goog
> 


^ permalink raw reply	[flat|nested] 3+ messages in thread

* Re: [PATCH] perf stat: Fix segfault on armv8_pmu events
  2020-10-07 11:42 ` Jiri Olsa
@ 2020-10-07 13:00   ` Arnaldo Carvalho de Melo
  0 siblings, 0 replies; 3+ messages in thread
From: Arnaldo Carvalho de Melo @ 2020-10-07 13:00 UTC (permalink / raw)
  To: Jiri Olsa
  Cc: Namhyung Kim, Ingo Molnar, Peter Zijlstra, Mark Rutland,
	Alexander Shishkin, LKML, Stephane Eranian, Wei Li, Barry Song

Em Wed, Oct 07, 2020 at 01:42:19PM +0200, Jiri Olsa escreveu:
> On Wed, Oct 07, 2020 at 05:13:11PM +0900, Namhyung Kim wrote:
> > It was reported that perf stat crashed when using with armv8_pmu (cpu)
> > events with the task mode.  As perf stat uses an empty cpu map for
> > task mode but armv8_pmu has its own cpu mask, it confused which map
> > should use when accessing file descriptors and caused segfaults:
> > 
> >   (gdb) bt
> >   #0  0x0000000000603fc8 in perf_evsel__close_fd_cpu (evsel=<optimized out>,
> >       cpu=<optimized out>) at evsel.c:122
> >   #1  perf_evsel__close_cpu (evsel=evsel@entry=0x716e950, cpu=7) at evsel.c:156
> >   #2  0x00000000004d4718 in evlist__close (evlist=0x70a7cb0) at util/evlist.c:1242
> >   #3  0x0000000000453404 in __run_perf_stat (argc=3, argc@entry=1, argv=0x30,
> >       argv@entry=0xfffffaea2f90, run_idx=119, run_idx@entry=1701998435)
> >       at builtin-stat.c:929
> >   #4  0x0000000000455058 in run_perf_stat (run_idx=1701998435, argv=0xfffffaea2f90,
> >       argc=1) at builtin-stat.c:947
> >   #5  cmd_stat (argc=1, argv=0xfffffaea2f90) at builtin-stat.c:2357
> >   #6  0x00000000004bb888 in run_builtin (p=p@entry=0x9764b8 <commands+288>,
> >       argc=argc@entry=4, argv=argv@entry=0xfffffaea2f90) at perf.c:312
> >   #7  0x00000000004bbb54 in handle_internal_command (argc=argc@entry=4,
> >       argv=argv@entry=0xfffffaea2f90) at perf.c:364
> >   #8  0x0000000000435378 in run_argv (argcp=<synthetic pointer>,
> >       argv=<synthetic pointer>) at perf.c:408
> >   #9  main (argc=4, argv=0xfffffaea2f90) at perf.c:538
> > 
> > To fix this, I simply used the given cpu map unless the evsel actually
> > is not a system-wide event (like uncore events).
> > 
> > Reported-by: Wei Li <liwei391@huawei.com>
> > Tested-by: Barry Song <song.bao.hua@hisilicon.com>
> > Fixes: 7736627b865d ("perf stat: Use affinity for closing file descriptors")
> > Signed-off-by: Namhyung Kim <namhyung@kernel.org>
> 
> Acked-by: Jiri Olsa <jolsa@redhat.com>

Thanks, applied.

- Arnaldo

 
> thanks,
> jirka
> 
> > ---
> >  tools/lib/perf/evlist.c | 3 +++
> >  1 file changed, 3 insertions(+)
> > 
> > diff --git a/tools/lib/perf/evlist.c b/tools/lib/perf/evlist.c
> > index 2208444ecb44..cfcdbd7be066 100644
> > --- a/tools/lib/perf/evlist.c
> > +++ b/tools/lib/perf/evlist.c
> > @@ -45,6 +45,9 @@ static void __perf_evlist__propagate_maps(struct perf_evlist *evlist,
> >  	if (!evsel->own_cpus || evlist->has_user_cpus) {
> >  		perf_cpu_map__put(evsel->cpus);
> >  		evsel->cpus = perf_cpu_map__get(evlist->cpus);
> > +	} else if (!evsel->system_wide && perf_cpu_map__empty(evlist->cpus)) {
> > +		perf_cpu_map__put(evsel->cpus);
> > +		evsel->cpus = perf_cpu_map__get(evlist->cpus);
> >  	} else if (evsel->cpus != evsel->own_cpus) {
> >  		perf_cpu_map__put(evsel->cpus);
> >  		evsel->cpus = perf_cpu_map__get(evsel->own_cpus);
> > -- 
> > 2.28.0.806.g8561365e88-goog
> > 
> 

-- 

- Arnaldo

^ permalink raw reply	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2020-10-07 13:00 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2020-10-07  8:13 [PATCH] perf stat: Fix segfault on armv8_pmu events Namhyung Kim
2020-10-07 11:42 ` Jiri Olsa
2020-10-07 13:00   ` Arnaldo Carvalho de Melo

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).