The worker is canceled in gt_park path, but earlier it was assumed that gt_park path cannot sleep and the cancel is asynchronous. This caused a race with suspend flow where the worker runs after suspend and causes an unclaimed register access warning. Cancel the worker synchronously since the gt_park is indeed allowed to sleep. v2: Fix author name and sign-off mismatch Signed-off-by: Umesh Nerlige Ramappa <umesh.nerlige.ramappa@xxxxxxxxx> Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/4419 Fixes: 77cdd054dd2c ("drm/i915/pmu: Connect engine busyness stats from GuC to pmu") --- drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c index 0d56b615bf78..e6275380b253 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_guc_submission.c @@ -1438,7 +1438,12 @@ void intel_guc_busyness_park(struct intel_gt *gt) if (!guc_submission_initialized(guc)) return; - cancel_delayed_work(&guc->timestamp.work); + /* + * There is a race with suspend flow where the worker runs after suspend + * and causes an unclaimed register access warning. Cancel the worker + * synchronously here. + */ + cancel_delayed_work_sync(&guc->timestamp.work); /* * Before parking, we should sample engine busyness stats if we need to. -- 2.25.1