diff --git a/block.c b/block.c
index 1c37ce4554..db0be7ef36 100644
--- a/block.c
+++ b/block.c
@@ -1924,6 +1924,8 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
     assert(role == &child_backing || role == &child_file);
 
     if (!backing) {
+        int flags = bdrv_reopen_get_flags(reopen_queue, bs);
+
         /* Apart from the modifications below, the same permissions are
          * forwarded and left alone as for filters */
         bdrv_filter_default_perms(bs, c, role, reopen_queue, perm, shared,
@@ -1936,7 +1938,9 @@ void bdrv_format_default_perms(BlockDriverState *bs, BdrvChild *c,
 
         /* bs->file always needs to be consistent because of the metadata. We
          * can never allow other users to resize or write to it. */
-        perm |= BLK_PERM_CONSISTENT_READ;
+        if (!(flags & BDRV_O_NO_IO)) {
+            perm |= BLK_PERM_CONSISTENT_READ;
+        }
         shared &= ~(BLK_PERM_WRITE | BLK_PERM_RESIZE);
     } else {
         /* We want consistent read from backing files if the parent needs it.