[PATCH 1/2] drm/scheduler: fix fence ref counting

[Andrey Grodzovsky]

Series is Reviewed-by: Andrey Grodzovsky <andrey.grodzovsky at amd.com>

Andrey

On 2022-09-29 14:01, Christian König wrote:
> We leaked dependency fences when processes were beeing killed.
>
> Additional to that grab a reference to the last scheduled fence.
>
> Signed-off-by: Christian König <christian.koenig at amd.com>
> ---
>   drivers/gpu/drm/scheduler/sched_entity.c | 6 +++++-
>   1 file changed, 5 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_entity.c b/drivers/gpu/drm/scheduler/sched_entity.c
> index 6b25b2f4f5a3..7ef1a086a6fb 100644
> --- a/drivers/gpu/drm/scheduler/sched_entity.c
> +++ b/drivers/gpu/drm/scheduler/sched_entity.c
> @@ -207,6 +207,7 @@ static void drm_sched_entity_kill_jobs_cb(struct dma_fence *f,
>   	struct drm_sched_job *job = container_of(cb, struct drm_sched_job,
>   						 finish_cb);
>   
> +	dma_fence_put(f);
>   	INIT_WORK(&job->work, drm_sched_entity_kill_jobs_work);
>   	schedule_work(&job->work);
>   }
> @@ -234,8 +235,10 @@ static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
>   		struct drm_sched_fence *s_fence = job->s_fence;
>   
>   		/* Wait for all dependencies to avoid data corruptions */
> -		while ((f = drm_sched_job_dependency(job, entity)))
> +		while ((f = drm_sched_job_dependency(job, entity))) {
>   			dma_fence_wait(f, false);
> +			dma_fence_put(f);
> +		}
>   
>   		drm_sched_fence_scheduled(s_fence);
>   		dma_fence_set_error(&s_fence->finished, -ESRCH);
> @@ -250,6 +253,7 @@ static void drm_sched_entity_kill_jobs(struct drm_sched_entity *entity)
>   			continue;
>   		}
>   
> +		dma_fence_get(entity->last_scheduled);
>   		r = dma_fence_add_callback(entity->last_scheduled,
>   					   &job->finish_cb,
>   					   drm_sched_entity_kill_jobs_cb);