diff --git a/grub-core/kern/main.c b/grub-core/kern/main.c
index 9cad0c448..682d598f1 100644
--- a/grub-core/kern/main.c
+++ b/grub-core/kern/main.c
@@ -131,6 +131,9 @@ grub_set_prefix_and_root (void)
     {
       char *cmdpath;
 
+      grub_env_set ("cmddevice", fwdevice);
+      grub_env_export ("cmddevice");
+
       cmdpath = grub_xasprintf ("(%s)%s", fwdevice, fwpath ? : "");
       if (cmdpath)
 	{