releases/4.19.29/perf-script-fix-crash-with-printing-mixed-trace-poin.patch

   1 From 99e92a69ece6aacaaf6c08be49fabfbfd5810717 Mon Sep 17 00:00:00 2001
   2 From: Andi Kleen <ak@linux.intel.com>
   3 Date: Thu, 17 Jan 2019 11:48:34 -0800
   4 Subject: perf script: Fix crash with printing mixed trace point and other
   5  events
   6
   7 [ Upstream commit 96167167b6e17b25c0e05ecc31119b73baeab094 ]
   8
   9 'perf script' crashes currently when printing mixed trace points and
  10 other events because the trace format does not handle events without
  11 trace meta data. Add a simple check to avoid that.
  12
  13   % cat > test.c
  14   main()
  15   {
  16       printf("Hello world\n");
  17   }
  18   ^D
  19   % gcc -g -o test test.c
  20   % sudo perf probe -x test 'test.c:3'
  21   % perf record -e '{cpu/cpu-cycles,period=10000/,probe_test:main}:S' ./test
  22   % perf script
  23   <segfault>
  24
  25 Committer testing:
  26
  27 Before:
  28
  29   # perf probe -x /lib64/libc-2.28.so malloc
  30   Added new event:
  31     probe_libc:malloc    (on malloc in /usr/lib64/libc-2.28.so)
  32
  33   You can now use it in all perf tools, such as:
  34
  35         perf record -e probe_libc:malloc -aR sleep 1
  36
  37   # perf probe -l
  38   probe_libc:malloc    (on __libc_malloc@malloc/malloc.c in /usr/lib64/libc-2.28.so)
  39   # perf record -e '{cpu/cpu-cycles,period=10000/,probe_libc:*}:S' sleep 1
  40   [ perf record: Woken up 1 times to write data ]
  41   [ perf record: Captured and wrote 0.023 MB perf.data (40 samples) ]
  42   # perf script
  43   Segmentation fault (core dumped)
  44   ^C
  45   #
  46
  47 After:
  48
  49   # perf script | head -6
  50      sleep 2888 94796.944981: 16198 cpu/cpu-cycles,period=10000/: ffffffff925dc04f get_random_u32+0x1f (/lib/modules/5.0.0-rc2+/build/vmlinux)
  51      sleep 2888 [-01] 94796.944981: probe_libc:malloc:
  52      sleep 2888 94796.944983:  4713 cpu/cpu-cycles,period=10000/: ffffffff922763af change_protection+0xcf (/lib/modules/5.0.0-rc2+/build/vmlinux)
  53      sleep 2888 [-01] 94796.944983: probe_libc:malloc:
  54      sleep 2888 94796.944986:  9934 cpu/cpu-cycles,period=10000/: ffffffff922777e0 move_page_tables+0x0 (/lib/modules/5.0.0-rc2+/build/vmlinux)
  55      sleep 2888 [-01] 94796.944986: probe_libc:malloc:
  56   #
  57
  58 Signed-off-by: Andi Kleen <ak@linux.intel.com>
  59 Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
  60 Acked-by: Jiri Olsa <jolsa@kernel.org>
  61 Link: http://lkml.kernel.org/r/20190117194834.21940-1-andi@firstfloor.org
  62 Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
  63 Signed-off-by: Sasha Levin <sashal@kernel.org>
  64 ---
  65  tools/perf/builtin-script.c | 2 +-
  66  1 file changed, 1 insertion(+), 1 deletion(-)
  67
  68 diff --git a/tools/perf/builtin-script.c b/tools/perf/builtin-script.c
  69 index 6c1e7ceedcf3..ce2aee11e360 100644
  70 --- a/tools/perf/builtin-script.c
  71 +++ b/tools/perf/builtin-script.c
  72 @@ -1658,7 +1658,7 @@ static void process_event(struct perf_script *script,
  73                 return;
  74         }
  75
  76 -       if (PRINT_FIELD(TRACE)) {
  77 +       if (PRINT_FIELD(TRACE) && sample->raw_data) {
  78                 event_format__fprintf(evsel->tp_format, sample->cpu,
  79                                       sample->raw_data, sample->raw_size, fp);
  80         }
  81 --
  82 2.19.1
  83