From: Christian König christian.koenig@amd.com
[ 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@amd.com Acked-by: Andrey Grodzovsky andrey.grodzovsky@amd.com Reviewed-by: Monk.liu@amd.com Signed-off-by: Alex Deucher alexander.deucher@amd.com Signed-off-by: Sasha Levin sashal@kernel.org --- 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.