[PATCH 4.18 080/197] perf arm spe: Fix uninitialized record error variable

From: Greg Kroah-Hartman
Date: Thu Sep 13 2018 - 09:58:58 EST


4.18-stable review patch. If anyone has any objections, please let me know.

------------------

From: Kim Phillips <kim.phillips@xxxxxxx>

[ Upstream commit 344353366591acf659a0d0dea498611da78d67e2 ]

The auxtrace init variable 'err' was not being initialized, leading perf
to abort early in an SPE record command when there was no explicit
error, rather only based whatever memory contents were on the stack.
Initialize it explicitly on getting an SPE successfully, the same way
cs-etm does.

Signed-off-by: Kim Phillips <kim.phillips@xxxxxxx>
Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Dongjiu Geng <gengdongjiu@xxxxxxxxxx>
Cc: Jiri Olsa <jolsa@xxxxxxxxxx>
Cc: Namhyung Kim <namhyung@xxxxxxxxxx>
Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
Fixes: ffd3d18c20b8 ("perf tools: Add ARM Statistical Profiling Extensions (SPE) support")
Link: http://lkml.kernel.org/r/20180810174512.52900813e57cbccf18ce99a2@xxxxxxx
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
tools/perf/arch/arm64/util/arm-spe.c | 1 +
1 file changed, 1 insertion(+)

--- a/tools/perf/arch/arm64/util/arm-spe.c
+++ b/tools/perf/arch/arm64/util/arm-spe.c
@@ -194,6 +194,7 @@ struct auxtrace_record *arm_spe_recordin
sper->itr.read_finish = arm_spe_read_finish;
sper->itr.alignment = 0;

+ *err = 0;
return &sper->itr;
}