diff --git a/grub-core/disk/ieee1275/ofdisk.c b/grub-core/disk/ieee1275/ofdisk.c
index 2cd43d80a..b4a8d969c 100644
--- a/grub-core/disk/ieee1275/ofdisk.c
+++ b/grub-core/disk/ieee1275/ofdisk.c
@@ -198,8 +198,14 @@ grub_ofdisk_iterate (int (*hook) (const char *name),
 	  if (grub_strncmp (ent->shortest, "cdrom", 5) == 0)
 	    continue;
 
-	  if (hook (ent->shortest))
-	    return 1;
+	  {
+	    char buffer[sizeof ("ieee1275/") + grub_strlen (env->shortest)];
+	    char *ptr;
+	    ptr = grub_stpcpy (buffer, "ieee1275/");
+	    grub_strcpy (ptr, env->shortest);
+	    if (hook (buffer))
+	      return 1;
+	  }
 	}
     }	  
   return 0;
@@ -241,7 +247,10 @@ grub_ofdisk_open (const char *name, grub_disk_t disk)
   char prop[64];
   grub_ssize_t actual;
 
-  devpath = compute_dev_path (name);
+  if (grub_strncmp (devpath, "ieee1275/", sizeof ("ieee1275/") - 1) != 0)
+      return grub_error (GRUB_ERR_UNKNOWN_DEVICE,
+			 "not IEEE1275 device");
+  devpath = compute_dev_path (name + sizeof ("ieee1275/") - 1);
   if (! devpath)
     return grub_errno;