Index: head/sys/vm/vm_object.c
===================================================================
--- head/sys/vm/vm_object.c
+++ head/sys/vm/vm_object.c
@@ -2225,8 +2225,6 @@
 vm_object_set_writeable_dirty(vm_object_t object)
 {
 
-	VM_OBJECT_ASSERT_LOCKED(object);
-
 	/* Only set for vnodes & tmpfs */
 	if (object->type != OBJT_VNODE &&
 	    (object->flags & OBJ_TMPFS_NODE) == 0)