qom: allow casting of a NULL class

[qemu.git] / block / mirror.c

diff --git a/block/mirror.c b/block/mirror.c
index a62ad86c28f7ce017d68dd42da3a71c2167d95de..8b07dec314812c77cc103e7158a6fb9e949d3480 100644 (file)
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -507,7 +507,7 @@ static void mirror_complete(BlockJob *job, Error **errp)
     MirrorBlockJob *s = container_of(job, MirrorBlockJob, common);
     int ret;
 
-    ret = bdrv_open_backing_file(s->target);
+    ret = bdrv_open_backing_file(s->target, NULL);
     if (ret < 0) {
         char backing_filename[PATH_MAX];
         bdrv_get_full_backing_filename(s->target, backing_filename,