diff --git a/src/libostree/ostree-repo.c b/src/libostree/ostree-repo.c
index 23b6dd2531..4996bd4670 100644
--- a/src/libostree/ostree-repo.c
+++ b/src/libostree/ostree-repo.c
@@ -3298,9 +3298,14 @@ static gboolean
 reload_sysroot_config (OstreeRepo *self, GCancellable *cancellable, GError **error)
 {
   g_autofree char *bootloader = NULL;
+#if !defined(__s390x__)
+  const char *default_bootloader = "auto";
+#else
+  const char *default_bootloader = "zipl";
+#endif
 
   if (!ot_keyfile_get_value_with_default_group_optional (self->config, "sysroot", "bootloader",
-                                                         "auto", &bootloader, error))
+                                                         default_bootloader, &bootloader, error))
     return FALSE;
 
   /* TODO: possibly later add support for specifying a generic bootloader