diff --git a/mm/backing-dev.c b/mm/backing-dev.c
index 4a9d4e27d0d9..8a46a0a4b72f 100644
--- a/mm/backing-dev.c
+++ b/mm/backing-dev.c
@@ -958,6 +958,7 @@ void bdi_unregister(struct backing_dev_info *bdi)
 		bdi->owner = NULL;
 	}
 }
+EXPORT_SYMBOL(bdi_unregister);
 
 static void release_bdi(struct kref *ref)
 {