[Nouveau] [PATCH] drm/nouveau: fix oops in display destructor with headless cards

[Maarten Lankhorst]

If init doesn't run then disp->outp might not be initialized, resulting in an oops.

Signed-off-by: Maarten Lankhorst <maarten.lankhorst at canonical.com>
---
diff --git a/drivers/gpu/drm/nouveau/core/engine/disp/base.c b/drivers/gpu/drm/nouveau/core/engine/disp/base.c
index c41f656abe64..9c38c5e40500 100644
--- a/drivers/gpu/drm/nouveau/core/engine/disp/base.c
+++ b/drivers/gpu/drm/nouveau/core/engine/disp/base.c
@@ -99,8 +99,10 @@ _nouveau_disp_dtor(struct nouveau_object *object)
 
 	nouveau_event_destroy(&disp->vblank);
 
-	list_for_each_entry_safe(outp, outt, &disp->outp, head) {
-		nouveau_object_ref(NULL, (struct nouveau_object **)&outp);
+	if (disp->outp.next) {
+		list_for_each_entry_safe(outp, outt, &disp->outp, head) {
+			nouveau_object_ref(NULL, (struct nouveau_object **)&outp);
+		}
 	}
 
 	nouveau_engine_destroy(&disp->base);