diff --git a/block/mirror.c b/block/mirror.c
index 20b3e8e5d825a1410b72834bbd312ae3af337263..2b48e6b09d5704ec56dbcda8a2c226401877f14a 100644
--- a/block/mirror.c
+++ b/block/mirror.c
@@ -934,7 +934,7 @@ static int coroutine_fn mirror_run(Job *job, Error **errp)
     MirrorBDSOpaque *mirror_top_opaque = s->mirror_top_bs->opaque;
     BlockDriverState *target_bs = blk_bs(s->target);
     bool need_drain = true;
-    BlockDeviceIoStatus iostatus;
+    BlockDeviceIoStatus iostatus = BLOCK_DEVICE_IO_STATUS__MAX;
     int64_t length;
     int64_t target_length;
     BlockDriverInfo bdi;