diff options
| author | Philipp Stanner <phasta@kernel.org> | 2025-10-24 18:12:22 +0200 |
|---|---|---|
| committer | Philipp Stanner <phasta@kernel.org> | 2025-10-27 13:58:56 +0100 |
| commit | e0023c8a74028739643aa14bd201c41a99866ca4 (patch) | |
| tree | a1ca1c268296dc9ddc85b3d804d985b68b7ce710 | |
| parent | d25e3a610bae03bffc5c14b5d944a5d0cd844678 (diff) | |
drm/nouveau: Fix race in nouveau_sched_fini()
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")
Acked-by: Danilo Krummrich <dakr@kernel.org>
Signed-off-by: Philipp Stanner <phasta@kernel.org>
Link: https://patch.msgid.link/20251024161221.196155-2-phasta@kernel.org
| -rw-r--r-- | drivers/gpu/drm/nouveau/nouveau_sched.c | 14 |
1 files 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); |