6.6-stable review patch. If anyone has any objections, please let me know.
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From: Maíra Canal mcanal@igalia.com
commit 61ee19dedb8d753249e20308782bf4e9e2fb7344 upstream.
Commit 704d3d60fec4 ("drm/etnaviv: don't block scheduler when GPU is still active") ensured that active jobs are returned to the pending list when extending the timeout. However, it didn't use the pending list's lock to manipulate the list, which causes a race condition as the scheduler's workqueues are running.
Hold the lock while manipulating the scheduler's pending list to prevent a race.
Cc: stable@vger.kernel.org Fixes: 704d3d60fec4 ("drm/etnaviv: don't block scheduler when GPU is still active") Reported-by: Philipp Stanner phasta@kernel.org Closes: https://lore.kernel.org/dri-devel/964e59ba1539083ef29b06d3c78f5e2e9b138ab8.c... Reviewed-by: Lucas Stach l.stach@pengutronix.de Reviewed-by: Philipp Stanner phasta@kernel.org Link: https://lore.kernel.org/r/20250602132240.93314-1-mcanal@igalia.com Signed-off-by: Maíra Canal mcanal@igalia.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/etnaviv/etnaviv_sched.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)
--- a/drivers/gpu/drm/etnaviv/etnaviv_sched.c +++ b/drivers/gpu/drm/etnaviv/etnaviv_sched.c @@ -34,6 +34,7 @@ static enum drm_gpu_sched_stat etnaviv_s *sched_job) { struct etnaviv_gem_submit *submit = to_etnaviv_submit(sched_job); + struct drm_gpu_scheduler *sched = sched_job->sched; struct etnaviv_gpu *gpu = submit->gpu; u32 dma_addr; int change; @@ -76,7 +77,9 @@ static enum drm_gpu_sched_stat etnaviv_s return DRM_GPU_SCHED_STAT_NOMINAL;
out_no_timeout: - list_add(&sched_job->list, &sched_job->sched->pending_list); + spin_lock(&sched->job_list_lock); + list_add(&sched_job->list, &sched->pending_list); + spin_unlock(&sched->job_list_lock); return DRM_GPU_SCHED_STAT_NOMINAL; }