drm/sched: Avoid data corruptions

Wait for all dependencies of a job  to complete before
killing it to avoid data corruptions.
Signed-off-by: Andrey Grodzovsky <andrey.grodzovsky@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210519141407.88444-1-andrey.grodzovsky@amd.com

drivers/gpu/drm/scheduler/sched_entity.c

@@ -222,11 +222,16 @@ static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
 static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
 {
 	struct drm_sched_job *job;
+	struct dma_fence *f;
 	int r;
 
 	while ((job = to_drm_sched_job(spsc_queue_pop(&entity->job_queue)))) {
 		struct drm_sched_fence *s_fence = job->s_fence;
 
+		/* Wait for all dependencies to avoid data corruptions */
+		while ((f = job->sched->ops->dependency(job, entity)))
+			dma_fence_wait(f, false);
+
 		drm_sched_fence_scheduled(s_fence);
 		dma_fence_set_error(&s_fence->finished, -ESRCH);