From: Christian König <christian.koenig@xxxxxxx> [ Upstream commit e1b4ce25dbc93ab0cb8ed0f236a3b9ff7b03802c ] The spsc_queue_peek function is accessing queue->head which belongs to the consumer thread and shouldn't be accessed by the producer This is fixing a rare race condition when destroying entities. Signed-off-by: Christian König <christian.koenig@xxxxxxx> Acked-by: Andrey Grodzovsky <andrey.grodzovsky@xxxxxxx> Reviewed-by: Monk.liu@xxxxxxx Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- drivers/gpu/drm/scheduler/sched_entity.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c index 35ddbec1375ae..671c90f34ede6 100644 --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -95,7 +95,7 @@ static bool drm_sched_entity_is_idle(struct drm_sched_entity *entity) rmb(); /* for list_empty to work without lock */ if (list_empty(&entity->list) || - spsc_queue_peek(&entity->job_queue) == NULL) + spsc_queue_count(&entity->job_queue) == 0) return true; return false; @@ -281,7 +281,7 @@ void drm_sched_entity_fini(struct drm_sched_entity *entity) /* Consumption of existing IBs wasn't completed. Forcefully * remove them here. */ - if (spsc_queue_peek(&entity->job_queue)) { + if (spsc_queue_count(&entity->job_queue)) { if (sched) { /* Park the kernel for a moment to make sure it isn't processing * our enity. -- 2.20.1 _______________________________________________ dri-devel mailing list dri-devel@xxxxxxxxxxxxxxxxxxxxx https://lists.freedesktop.org/mailman/listinfo/dri-devel