nouveau_sched_fini() uses a memory barrier before wait_event(). wait_event(), however, is a macro which expands to a loop which might check the passed condition several times. The barrier would only take effect for the first check.

Replace the barrier with a function which takes the spinlock.

Cc: stable@vger.kernel.org # v6.8+ Fixes: 5f03a507b29e ("drm/nouveau: implement 1:1 scheduler - entity relationship") Signed-off-by: Philipp Stanner phasta@kernel.org --- drivers/gpu/drm/nouveau/nouveau_sched.c | 14 ++++++++++++-- 1 file changed, 12 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/nouveau/nouveau_sched.c b/drivers/gpu/drm/nouveau/nouveau_sched.c index e60f7892f5ce..a7bf539e5d86 100644 --- a/drivers/gpu/drm/nouveau/nouveau_sched.c +++ b/drivers/gpu/drm/nouveau/nouveau_sched.c @@ -482,6 +482,17 @@ nouveau_sched_create(struct nouveau_sched **psched, struct nouveau_drm *drm, return 0; }

+static bool +nouveau_sched_job_list_empty(struct nouveau_sched *sched) +{ + bool empty; + + spin_lock(&sched->job.list.lock); + empty = list_empty(&sched->job.list.head); + spin_unlock(&sched->job.list.lock); + + return empty; +}

static void nouveau_sched_fini(struct nouveau_sched *sched) @@ -489,8 +500,7 @@ nouveau_sched_fini(struct nouveau_sched *sched) struct drm_gpu_scheduler *drm_sched = &sched->base; struct drm_sched_entity *entity = &sched->entity;

- rmb(); /* for list_empty to work without lock */ - wait_event(sched->job.wq, list_empty(&sched->job.list.head)); + wait_event(sched->job.wq, nouveau_sched_job_list_empty(sched));

drm_sched_entity_fini(entity); drm_sched_fini(drm_sched);