From b7d2a4da38fb558832b70c6f45929649a9d114a3 Mon Sep 17 00:00:00 2001 From: John Harrison Date: Mon, 13 Nov 2023 17:00:15 -0800 Subject: [PATCH] drm/i915/guc: Fix for potential false positives in GuC hang selftest Noticed that the hangcheck selftest is submitting a non-preemptoble spinner. That means that even if the GuC does not die, the heartbeat will still kick in and trigger a reset. Which is rather defeating the purpose of the test - to verify that the heartbeat will kick in if the GuC itself has died. The test is deliberately killing the GuC, so it should never hit the case of a non-dead GuC. But it is not impossible that the kill might fail at some future point due to other driver re-work. So, make the spinner pre-emptible. That way the heartbeat can get through if the GuC is alive and context switching. Thus a reset only happens if the GuC dies. Thus, if the kill should stop working the test will now fail rather than claim to pass. Signed-off-by: John Harrison Reviewed-by: Daniele Ceraolo Spurio Link: https://patchwork.freedesktop.org/patch/msgid/20231114010016.234570-2-John.C.Harrison@Intel.com --- drivers/gpu/drm/i915/gt/uc/selftest_guc_hangcheck.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/uc/selftest_guc_hangcheck.c b/drivers/gpu/drm/i915/gt/uc/selftest_guc_hangcheck.c index 34b5d952e2bc..26fdc392fce6 100644 --- a/drivers/gpu/drm/i915/gt/uc/selftest_guc_hangcheck.c +++ b/drivers/gpu/drm/i915/gt/uc/selftest_guc_hangcheck.c @@ -74,7 +74,7 @@ static int intel_hang_guc(void *arg) goto err; } - rq = igt_spinner_create_request(&spin, ce, MI_NOOP); + rq = igt_spinner_create_request(&spin, ce, MI_ARB_CHECK); intel_context_put(ce); if (IS_ERR(rq)) { ret = PTR_ERR(rq); -- 2.25.1