diff --git a/src/libostree/ostree-impl-system-generator.c b/src/libostree/ostree-impl-system-generator.c
index e51584cda8..d8463171a4 100644
--- a/src/libostree/ostree-impl-system-generator.c
+++ b/src/libostree/ostree-impl-system-generator.c
@@ -261,17 +261,17 @@ _ostree_impl_system_generator (const char *normal_dir, const char *early_dir, co
   if (!cmdline)
     return glnx_throw (error, "Failed to read /proc/cmdline");
 
-  g_autofree char *ostree_cmdline = otcore_find_proc_cmdline_key (cmdline, "ostree");
-
+  g_autoptr (GError) otcore_get_ostree_target_error = NULL;
+  g_autofree char *ostree_target = NULL;
   /* This could happen in CoreOS live environments, where we hackily mock
    * the `ostree=` karg for `ostree-prepare-root.service` specifically, but
    * otherwise that karg doesn't exist on the real command-line. */
-  if (!ostree_cmdline)
+  if (!otcore_get_ostree_target (cmdline, &ostree_target, &otcore_get_ostree_target_error))
     return TRUE;
 
   if (!require_internal_units (normal_dir, early_dir, late_dir, error))
     return FALSE;
-  if (!fstab_generator (ostree_cmdline, normal_dir, early_dir, late_dir, error))
+  if (!fstab_generator (ostree_target, normal_dir, early_dir, late_dir, error))
     return FALSE;
 
   return TRUE;