[PATCH 3/3] perf script: Fix crash because of missing feat_op[] entry

From: Ravi Bangoria
Date: Wed Jun 20 2018 - 09:31:14 EST


perf_event__process_feature() tries to access feat_ops[feat].process
which is not defined for feat = HEADER_LAST_FEATURE and thus perf is
crashing. Add dummy entry for HEADER_LAST_FEATURE in the feat_ops.

Before:
# ./perf record -o - ls | ./perf script
Segmentation fault (core dumped)

After:
# ./perf record -o - ls | ./perf script
ls 7031 4392.099856: 250000 cpu-clock:uhH: 7f5e0ce7cd60
ls 7031 4392.100355: 250000 cpu-clock:uhH: 7f5e0c706ef7

Signed-off-by: Ravi Bangoria <ravi.bangoria@xxxxxxxxxxxxx>
Fixes: 57b5de463925 ("perf report: Support forced leader feature in pipe mode")
---
tools/perf/util/header.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/tools/perf/util/header.c b/tools/perf/util/header.c
index 540cd2dcd3e7..de8e3e29d870 100644
--- a/tools/perf/util/header.c
+++ b/tools/perf/util/header.c
@@ -2555,14 +2555,18 @@ struct feature_ops {
}

/* feature_ops not implemented: */
+#define write_last_feature NULL
+
#define print_tracing_data NULL
#define print_build_id NULL
+#define print_last_feature NULL

#define process_branch_stack NULL
#define process_stat NULL
+#define process_last_feature NULL


-static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
+static const struct feature_ops feat_ops[HEADER_LAST_FEATURE + 1] = {
FEAT_OPN(TRACING_DATA, tracing_data, false),
FEAT_OPN(BUILD_ID, build_id, false),
FEAT_OPR(HOSTNAME, hostname, false),
@@ -2585,6 +2589,7 @@ static const struct feature_ops feat_ops[HEADER_LAST_FEATURE] = {
FEAT_OPN(CACHE, cache, true),
FEAT_OPR(SAMPLE_TIME, sample_time, false),
FEAT_OPR(MEM_TOPOLOGY, mem_topology, true),
+ FEAT_OPN(LAST_FEATURE, last_feature, false),
};

struct header_print_data {
--
2.14.4