From: Arnaldo Carvalho de Melo <a...@redhat.com>

It was just freezing instead of informing about the SEGV, fix it and
also print a backtrace, just like in the TUI mode and in 'perf trace'.

Tested by provoking a NULL deref when pressing 'z':

     0.31%  libc-2.20.so     [.] malloc_consolidate
     0.31%  ld-2.20.so       [.] _dl_relocate_object
     0.28%  cc1              [.] ht_lookup
     0.28%  cc1              [.] ira_init_register_move_cost
  perf: Segmentation fault
  Obtained 7 stack frames.
  perf(dump_stack+0x32) [0x4d69f2]
  perf(sighandler_dump_stack+0x29) [0x4d6a89]
  /lib64/libc.so.6(+0x34960) [0x7f5064333960]
  perf() [0x438790]
  /lib64/libpthread.so.0(+0x752a) [0x7f50663dd52a]
  /lib64/libc.so.6(clone+0x6d) [0x7f50643ff22d]
  #

Reported-by: Linus Torvalds <torva...@linux-foundation.org>
Cc: Adrian Hunter <adrian.hun...@intel.com>
Cc: Borislav Petkov <b...@suse.de>
Cc: David Ahern <dsah...@gmail.com>
Cc: Frederic Weisbecker <fweis...@gmail.com>
Cc: Jiri Olsa <jo...@redhat.com>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Stephane Eranian <eran...@google.com>
Link: http://lkml.kernel.org/n/tip-pewrpzqd29rgmhu2wkk7f...@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com>
---
 tools/perf/builtin-top.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index ecf319728f25..6135cc07213c 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -601,8 +601,8 @@ static void display_sig(int sig __maybe_unused)
 
 static void display_setup_sig(void)
 {
-       signal(SIGSEGV, display_sig);
-       signal(SIGFPE,  display_sig);
+       signal(SIGSEGV, sighandler_dump_stack);
+       signal(SIGFPE, sighandler_dump_stack);
        signal(SIGINT,  display_sig);
        signal(SIGQUIT, display_sig);
        signal(SIGTERM, display_sig);
-- 
2.1.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to