--- a/grub-core/osdep/linux/getroot.c
+++ b/grub-core/osdep/linux/getroot.c
@@ -740,6 +740,10 @@
   if (! realpath (os_dev, path))
     return NULL;
 
+#ifdef __s390x__
+  return path;
+#endif
+
   if (strncmp ("/dev/", path, 5) == 0)
     {
       char *p = path + 5;
