Index: head/sys/kern/kern_exec.c
===================================================================
--- head/sys/kern/kern_exec.c
+++ head/sys/kern/kern_exec.c
@@ -1091,6 +1091,10 @@
 		shmexit(vmspace);
 		pmap_remove_pages(vmspace_pmap(vmspace));
 		vm_map_remove(map, vm_map_min(map), vm_map_max(map));
+		/* An exec terminates mlockall(MCL_FUTURE). */
+		vm_map_lock(map);
+		vm_map_modflags(map, 0, MAP_WIREFUTURE);
+		vm_map_unlock(map);
 	} else {
 		error = vmspace_exec(p, sv_minuser, sv->sv_maxuser);
 		if (error)
Index: head/sys/vm/vm_map.c
===================================================================
--- head/sys/vm/vm_map.c
+++ head/sys/vm/vm_map.c
@@ -3557,25 +3557,23 @@
 	return (vm2);
 }
 
+/*
+ * Create a process's stack for exec_new_vmspace().  This function is never
+ * asked to wire the newly created stack.
+ */
 int
 vm_map_stack(vm_map_t map, vm_offset_t addrbos, vm_size_t max_ssize,
     vm_prot_t prot, vm_prot_t max, int cow)
 {
 	vm_size_t growsize, init_ssize;
-	rlim_t lmemlim, vmemlim;
+	rlim_t vmemlim;
 	int rv;
 
+	MPASS((map->flags & MAP_WIREFUTURE) == 0);
 	growsize = sgrowsiz;
 	init_ssize = (max_ssize < growsize) ? max_ssize : growsize;
 	vm_map_lock(map);
-	lmemlim = lim_cur(curthread, RLIMIT_MEMLOCK);
 	vmemlim = lim_cur(curthread, RLIMIT_VMEM);
-	if (!old_mlock && map->flags & MAP_WIREFUTURE) {
-		if (ptoa(pmap_wired_count(map->pmap)) + init_ssize > lmemlim) {
-			rv = KERN_NO_SPACE;
-			goto out;
-		}
-	}
 	/* If we would blow our VMEM resource limit, no go */
 	if (map->size + init_ssize > vmemlim) {
 		rv = KERN_NO_SPACE;