[Patch v2 1/5] perf tests: Skip zero sample IP in object-code reading test

[Dapeng Mi]

The kernel may clear the sample IP to 0 when a user-space address is
expected but a kernel address is sampled due to hardware skid. A zero
sample IP causes the object-code reading test to fail incorrectly.

Skip zero sample IP values in the object-code reading test to avoid
false-positive failures.

Reported-by: kernel test robot <yi1.lai@xxxxxxxxx>
Closes: https://lore.kernel.org/oe-lkp/202609151503.cb02f753-lkp@xxxxxxxxx
Fixes: 166f10836a65 ("perf/core: Fix kernel register info leak via hardware skid")
Signed-off-by: Dapeng Mi <dapeng1.mi@xxxxxxxxxxxxxxx>
---
 tools/perf/tests/code-reading.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/tools/perf/tests/code-reading.c b/tools/perf/tests/code-reading.c
index 130cd6021f93..7b80c4ab6916 100644
--- a/tools/perf/tests/code-reading.c
+++ b/tools/perf/tests/code-reading.c
@@ -546,6 +546,11 @@ static int process_sample_event(struct machine *machine, struct evlist *evlist,
 		goto out;
 	}
 
+	if (!sample.ip) {
+		pr_debug("kernel may clear IP to 0 in invalid cases, skip it\n");
+		goto out;
+	}
+
 	thread = machine__findnew_thread(machine, sample.pid, sample.tid);
 	if (!thread) {
 		pr_debug("machine__findnew_thread failed\n");
-- 
2.34.1