vmwgfx: Allow reference and unreference of NULL fence objects.
The execbuf utils may call reference on NULL fence objects.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jakob Bornecrantz <jakob@vmware.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
diff --git a/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c b/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
index 5065a14..5f60be7 100644
--- a/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
+++ b/drivers/gpu/drm/vmwgfx/vmwgfx_fence.c
@@ -177,6 +177,9 @@
struct vmw_fence_obj *vmw_fence_obj_reference(struct vmw_fence_obj *fence)
{
+ if (unlikely(fence == NULL))
+ return NULL;
+
kref_get(&fence->kref);
return fence;
}
@@ -191,8 +194,12 @@
void vmw_fence_obj_unreference(struct vmw_fence_obj **fence_p)
{
struct vmw_fence_obj *fence = *fence_p;
- struct vmw_fence_manager *fman = fence->fman;
+ struct vmw_fence_manager *fman;
+ if (unlikely(fence == NULL))
+ return;
+
+ fman = fence->fman;
*fence_p = NULL;
spin_lock_irq(&fman->lock);
BUG_ON(atomic_read(&fence->kref.refcount) == 0);