Index: sys/kern/kern_descrip.c
===================================================================
--- sys/kern/kern_descrip.c
+++ sys/kern/kern_descrip.c
@@ -667,11 +667,7 @@
 			    flp, flg);
 			break;
 		case F_UNLCKSYS:
-			/*
-			 * Temporary api for testing remote lock
-			 * infrastructure.
-			 */
-			if (flg != F_REMOTE) {
+			if (flg != F_REMOTE || flp->l_sysid == 0) {
 				error = EINVAL;
 				break;
 			}