On 2015/12/2 23:49, Namhyung Kim wrote:
Hi,
On Wed, Dec 02, 2015 at 11:28:52AM +0000, Wang Nan wrote:
If feed perf a symbol filter in cmdline and the result is empty,
pressing 'Enter' in the hist browser causes crash:
# ./perf report perf.data <-- Common mistake for beginners
Then press 'Enter':
perf: Segmentation fault
-------- backtrace --------
/home/wangnan/perf[0x53e578]
/lib64/libc.so.6(+0x3545f)[0x7f76bafe045f]
/home/wangnan/perf[0x539dd4]
/home/wangnan/perf(perf_evlist__tui_browse_hists+0x96)[0x53d216]
/home/wangnan/perf(cmd_report+0x1b9f)[0x442c7f]
/home/wangnan/perf[0x47efa2]
/home/wangnan/perf(main+0x5f5)[0x432fa5]
/lib64/libc.so.6(__libc_start_main+0xf4)[0x7f76bafccbd4]
/home/wangnan/perf[0x4330d4]
This is because 'perf.data' is interperted as a symbol filter, and the
result is empty, so selection is empty. However,
hist_browser__toggle_fold() forgets to check it.
This patch simply return faluse when selection is NULL.
s/faluse/false/
Signed-off-by: Wang Nan <wangn...@huawei.com>
Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
Acked-by: Namhyung Kim <namhy...@kernel.org>
One nitpick below..
---
tools/perf/ui/browsers/hists.c | 5 ++++-
1 file changed, 4 insertions(+), 1 deletion(-)
diff --git a/tools/perf/ui/browsers/hists.c b/tools/perf/ui/browsers/hists.c
index dcdcbaf..33da341 100644
--- a/tools/perf/ui/browsers/hists.c
+++ b/tools/perf/ui/browsers/hists.c
@@ -337,9 +337,12 @@ static bool hist_browser__toggle_fold(struct hist_browser
*browser)
{
struct hist_entry *he = browser->he_selection;
struct map_symbol *ms = browser->selection;
- struct callchain_list *cl = container_of(ms, struct callchain_list, ms);
+ struct callchain_list *cl = ms ? container_of(ms, struct
callchain_list, ms) : NULL;
I think this line is not needed as container_of doesn't make a pointer
dereference by itself. Just checking below is enough IMHO.
I know it. Add it only for correctness.
Will be removed.
Thank you.
Thanks,
Namhyung
bool has_children;
+ if (!ms)
+ return false;
+
if (ms == &he->ms)
has_children = hist_entry__toggle_fold(he);
else
--
1.8.3.4
--
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/
