From: Junwei Zhang <Jerry.Zhang@amd.com>
Date: Mon, 16 Jul 2018 02:53:43 +0000 (+0800)
Subject: drm/scheduler: add NULL pointer check for run queue (v2)
X-Git-Tag: v4.19~298^2~25^2~27
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=a6da48caf92b4b6119cae146259528bec0e48545;p=platform%2Fkernel%2Flinux-rpi.git

drm/scheduler: add NULL pointer check for run queue (v2)

To check rq pointer before adding entity into it.
That avoids NULL pointer access in some case.

v2: move the check to caller

Suggested-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Junwei Zhang <Jerry.Zhang@amd.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
---

diff --git a/drivers/gpu/drm/scheduler/gpu_scheduler.c b/drivers/gpu/drm/scheduler/gpu_scheduler.c
index 16bf446..dac71e3 100644
--- a/drivers/gpu/drm/scheduler/gpu_scheduler.c
+++ b/drivers/gpu/drm/scheduler/gpu_scheduler.c
@@ -547,6 +547,11 @@ void drm_sched_entity_push_job(struct drm_sched_job *sched_job,
 	if (first) {
 		/* Add the entity to the run queue */
 		spin_lock(&entity->rq_lock);
+		if (!entity->rq) {
+			DRM_ERROR("Trying to push to a killed entity\n");
+			spin_unlock(&entity->rq_lock);
+			return;
+		}
 		drm_sched_rq_add_entity(entity->rq, entity);
 		spin_unlock(&entity->rq_lock);
 		drm_sched_wakeup(sched);