[PATCH AUTOSEL for 4.9 023/219] perf sort: Fix segfault with basic block 'cycles' sort dimension

Sasha Levin
2018-03-03T22:31:23Z

From: Changbin Du <changbin.du@intel.com>

[ Upstream commit 4b0b3aa6a2756e6115fdf275c521e4552a7082f3 ]

Skip the sample which doesn't have branch_info to avoid segmentation
fault:

The fault can be reproduced by:

perf record -a
perf report -F cycles

Signed-off-by: Changbin Du <changbin.du@intel.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Fixes: 0e332f033a82 ("perf tools: Add support for cycles, weight branch_info field")
Link: http://lkml.kernel.org/r/20170313083148.23568-1-changbin.du@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Sasha Levin <alexander.levin@microsoft.com>
---
tools/perf/util/sort.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/tools/perf/util/sort.c b/tools/perf/util/sort.c
index 452e15a10dd2..031e64ce7156 100644
--- a/tools/perf/util/sort.c
+++ b/tools/perf/util/sort.c
@@ -846,6 +846,9 @@ static int hist_entry__mispredict_snprintf(struct hist_entry *he, char *bf,
static int64_t
sort__cycles_cmp(struct hist_entry *left, struct hist_entry *right)
{
+ if (!left->branch_info || !right->branch_info)
+ return cmp_null(left->branch_info, right->branch_info);
+
return left->branch_info->flags.cycles -
right->branch_info->flags.cycles;
}
@@ -853,6 +856,8 @@ sort__cycles_cmp(struct hist_entry *left, struct hist_entry *right)
static int hist_entry__cycles_snprintf(struct hist_entry *he, char *bf,
size_t size, unsigned int width)
{
+ if (!he->branch_info)
+ return scnprintf(bf, size, "%-.*s", width, "N/A");
if (he->branch_info->flags.cycles == 0)
return repsep_snprintf(bf, size, "%-*s", width, "-");
return repsep_snprintf(bf, size, "%-*hd", width,
--
2.14.1