ttm: Don't return the bo reserved on error path

An unlikely race could case a bo to be returned reserved on an error path.

Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Reviewed-by: Jerome Glisse <jglisse@redhat.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

diff --git a/drivers/gpu/drm/ttm/ttm_bo.c b/drivers/gpu/drm/ttm/ttm_bo.c
index 617b64678fc62f24c70df6ae3fd7ba3bc7d6c9bf..0bb0f5f713e6cf9166a1b91eb19ab81b85206716 100644 (file)
--- a/drivers/gpu/drm/ttm/ttm_bo.c
+++ b/drivers/gpu/drm/ttm/ttm_bo.c
@@ -574,10 +574,16 @@ retry:
                return ret;
 
        spin_lock(&glob->lru_lock);
+
+       if (unlikely(list_empty(&bo->ddestroy))) {
+               spin_unlock(&glob->lru_lock);
+               return 0;
+       }
+
        ret = ttm_bo_reserve_locked(bo, interruptible,
                                    no_wait_reserve, false, 0);
 
-       if (unlikely(ret != 0) || list_empty(&bo->ddestroy)) {
+       if (unlikely(ret != 0)) {
                spin_unlock(&glob->lru_lock);
                return ret;
        }