From: Namhyung Kim namhyung@kernel.org
[ Upstream commit bef69bd7cfc363ab94b84ea29102f3e913ed3c6c ]
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 has confused which map it should use when accessing file descriptors and this causes 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).
Fixes: 7736627b865d ("perf stat: Use affinity for closing file descriptors") Reported-by: Wei Li liwei391@huawei.com Signed-off-by: Namhyung Kim namhyung@kernel.org Tested-by: Barry Song song.bao.hua@hisilicon.com Acked-by: Jiri Olsa jolsa@redhat.com Cc: Alexander Shishkin alexander.shishkin@linux.intel.com Cc: Mark Rutland mark.rutland@arm.com Cc: Peter Zijlstra peterz@infradead.org Cc: Stephane Eranian eranian@google.com Link: http://lore.kernel.org/lkml/20201007081311.1831003-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo acme@redhat.com Signed-off-by: Sasha Levin sashal@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 6a875a0f01bb0..233592c5a52c7 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);