On 27 Feb 2025, at 6:08 AM, Namhyung Kim [off-list ref] wrote:

On Tue, Feb 25, 2025 at 05:01:57PM +0530, Athira Rajeev wrote:

quoted

Perf trace on perf.data fails as below:

./perf trace record -- sleep 1
./perf trace -i perf.data
perf: Segmentation fault
Segmentation fault (core dumped)

Backtrace pointed to :
?? ()
perf_session.process_user_event ()
reader.read_event ()
perf_session.process_events ()
cmd_trace ()
run_builtin ()
handle_internal_command ()
main ()

Further debug pointed that, segmentation fault happens when
trying to access id_index. Code snippet:

case PERF_RECORD_ID_INDEX:
err = tool->id_index(session, event);

Since 'commit 15d4a6f41d72 ("perf tool: Remove
perf_tool__fill_defaults()")', perf_tool__fill_defaults is
removed. All tools are initialized using perf_tool__init()
prior to use. But in builtin-trace, perf_tool__init is not
used and hence the defaults are not initialized. Use
perf_tool__init() in perf trace to handle the initialization.

Thanks for fixing this.  I can reproduce the problem and confirmed this
patch fixed it.

Thanks,
Namhyung

Thanks Namhyung for checking the patch

Athira

quoted

Reported-by: Tejas Manhas <redacted>
Signed-off-by: Athira Rajeev <redacted>
---
tools/perf/builtin-trace.c | 1 +
1 file changed, 1 insertion(+)

diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c
index f55a8a6481f2..092c5f6404ba 100644
--- a/tools/perf/builtin-trace.c
+++ b/tools/perf/builtin-trace.c

@@ -4589,6 +4589,7 @@ static int trace__replay(struct trace *trace)

struct evsel *evsel;
int err = -1;

+ perf_tool__init(&trace->tool, /*ordered_events=*/true);
trace->tool.sample   = trace__process_sample;
trace->tool.mmap   = perf_event__process_mmap;
trace->tool.mmap2   = perf_event__process_mmap2;
-- 
2.43.5