diff --git a/blockdev-nbd.c b/blockdev-nbd.c
index 274fba6..e362572 100644
--- a/blockdev-nbd.c
+++ b/blockdev-nbd.c
@@ -93,6 +93,13 @@
         return;
     }
 
+    if (!has_writable) {
+        writable = true;
+    }
+    if (bdrv_is_read_only(bs)) {
+        writable = false;
+    }
+
     exp = nbd_export_new(bs, 0, -1, writable ? 0 : NBD_FLAG_READ_ONLY,
                          nbd_server_put_ref);