From: Frederic Weisbecker on
The raw_field_ptr() helper, used to retrieve the address of a field
inside a trace event, treats every strings as if they were dynamic
ie: having a secondary level of indirection to retrieve their

FIELD_IS_STRING doesn't mean FIELD_IS_DYNAMIC, we only need to
compute the secondary dereference for the latter case.

This fixes perf sched segfaults, bad cmdline report and may be
some other bugs.

Reported-by: Jason Baron <jbaron(a)>
Reported-by: Arnaldo Carvalho de Melo <acme(a)>
Signed-off-by: Frederic Weisbecker <fweisbec(a)>
Cc: Ingo Molnar <mingo(a)>
Cc: Peter Zijlstra <a.p.zijlstra(a)>
Cc: Paul Mackerras <paulus(a)>
Cc: Tom Zanussi <tzanussi(a)>
tools/perf/util/trace-event-parse.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/tools/perf/util/trace-event-parse.c b/tools/perf/util/trace-event-parse.c
index 069f261..73a0222 100644
--- a/tools/perf/util/trace-event-parse.c
+++ b/tools/perf/util/trace-event-parse.c
@@ -1937,7 +1937,7 @@ void *raw_field_ptr(struct event *event, const char *name, void *data)
if (!field)
return NULL;

- if (field->flags & FIELD_IS_STRING) {
+ if (field->flags & FIELD_IS_DYNAMIC) {
int offset;

offset = *(int *)(data + field->offset);

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