On Tue, Nov 16, 2021 at 10:25:19AM +0100, Christian König wrote:
> We need to grab another ref before trying to add the fence to the sched
> job and not after.
>
> Signed-off-by: Christian König <christian.koenig@xxxxxxx>
Reviewed-by: Daniel Vetter <daniel.vetter@xxxxxxxx>
I wondered first why this goes boom, but then I realized that in some
cases add_dependency() drops the reference of the passed-in fence.
Please also add the Fixes: line like in the previous patch.
Cheers, Daniel
> ---
> drivers/gpu/drm/scheduler/sched_main.c | 10 ++++++----
> 1 file changed, 6 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/gpu/drm/scheduler/sched_main.c b/drivers/gpu/drm/scheduler/sched_main.c
> index 94fe51b3caa2..400d201c3c28 100644
> --- a/drivers/gpu/drm/scheduler/sched_main.c
> +++ b/drivers/gpu/drm/scheduler/sched_main.c
> @@ -704,12 +704,14 @@ int drm_sched_job_add_implicit_dependencies(struct drm_sched_job *job,
> int ret;
>
> dma_resv_for_each_fence(&cursor, obj->resv, write, fence) {
> - ret = drm_sched_job_add_dependency(job, fence);
> - if (ret)
> - return ret;
> -
> /* Make sure to grab an additional ref on the added fence */
> dma_fence_get(fence);
> +
> + ret = drm_sched_job_add_dependency(job, fence);
> + if (ret) {
> + dma_fence_put(fence);
> + return ret;
> + }
> }
> return 0;
> }
> --
> 2.25.1
>
--
Daniel Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
