--- /usr/src/stand/efi/libefi/devicename.c.orig	2018-03-15 08:22:46.000000000 +0900
+++ /usr/src/stand/efi/libefi/devicename.c	2018-07-16 20:08:44.607332000 +0900
@@ -59,7 +59,7 @@
 	 * use the current device instead.
 	 */
 	if (devspec == NULL || *devspec == '/' || !strchr(devspec, ':')) {
-		rv = efi_parsedev(dev, getenv("currdev"), NULL);
+		rv = efi_parsedev(dev, getenv("rootdev") ? getenv("rootdev") : getenv("currdev"), NULL);
 		if (rv == 0 && path != NULL)
 			*path = devspec;
 		return (rv);