6.1-stable review patch. If anyone has any objections, please let me know.
------------------ From: Tvrtko Ursulin <tvrtko.ursu...@igalia.com> commit 4286cc2c953983d44d248c9de1c81d3a9643345c upstream. Without the locking amdgpu currently can race between amdgpu_ctx_set_entity_priority() (via drm_sched_entity_modify_sched()) and drm_sched_job_arm(), leading to the latter accesing potentially inconsitent entity->sched_list and entity->num_sched_list pair. v2: * Improve commit message. (Philipp) Signed-off-by: Tvrtko Ursulin <tvrtko.ursu...@igalia.com> Fixes: b37aced31eb0 ("drm/scheduler: implement a function to modify sched list") Cc: Christian König <christian.koe...@amd.com> Cc: Alex Deucher <alexander.deuc...@amd.com> Cc: Luben Tuikov <ltuiko...@gmail.com> Cc: Matthew Brost <matthew.br...@intel.com> Cc: David Airlie <airl...@gmail.com> Cc: Daniel Vetter <dan...@ffwll.ch> Cc: dri-devel@lists.freedesktop.org Cc: Philipp Stanner <pstan...@redhat.com> Cc: <sta...@vger.kernel.org> # v5.7+ Reviewed-by: Christian König <christian.koe...@amd.com> Link: https://patchwork.freedesktop.org/patch/msgid/20240913160559.49054-2-tursu...@igalia.com Signed-off-by: Christian König <christian.koe...@amd.com> Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org> --- drivers/gpu/drm/scheduler/sched_entity.c | 2 ++ 1 file changed, 2 insertions(+) --- a/drivers/gpu/drm/scheduler/sched_entity.c +++ b/drivers/gpu/drm/scheduler/sched_entity.c @@ -110,8 +110,10 @@ void drm_sched_entity_modify_sched(struc { WARN_ON(!num_sched_list || !sched_list); + spin_lock(&entity->rq_lock); entity->sched_list = sched_list; entity->num_sched_list = num_sched_list; + spin_unlock(&entity->rq_lock); } EXPORT_SYMBOL(drm_sched_entity_modify_sched);