From: Junwei Zhang <Jerry.Zhang@amd.com>
Date: Mon, 16 Jul 2018 10:53:43 +0800
Subject: drm/scheduler: add NULL pointer check for run queue (v2)
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Git-commit: a6da48caf92b4b6119cae146259528bec0e48545
Patch-mainline: v4.19-rc1
References: FATE#326289 FATE#326079 FATE#326049 FATE#322398 FATE#326166

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>
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
 drivers/gpu/drm/scheduler/gpu_scheduler.c |    5 +++++
 1 file changed, 5 insertions(+)

--- 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 dr
 	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);