Index: sys/kern/vfs_subr.c
===================================================================
--- sys/kern/vfs_subr.c
+++ sys/kern/vfs_subr.c
@@ -3098,6 +3098,7 @@
 vflush(struct mount *mp, int rootrefs, int flags, struct thread *td)
 {
 	struct vnode *vp, *mvp, *rootvp = NULL;
+	struct vm_object *obj;
 	struct vattr vattr;
 	int busy = 0, error;
 
@@ -3140,10 +3141,12 @@
 		 * vnodes open for writing.
 		 */
 		if (flags & WRITECLOSE) {
-			if (vp->v_object != NULL) {
-				VM_OBJECT_WLOCK(vp->v_object);
-				vm_object_page_clean(vp->v_object, 0, 0, 0);
-				VM_OBJECT_WUNLOCK(vp->v_object);
+			obj = vp->v_object;
+			if (obj != NULL &&
+			    (obj->flags & OBJ_MIGHTBEDIRTY) != 0) {
+				VM_OBJECT_WLOCK(obj);
+				vm_object_page_clean(obj, 0, 0, 0);
+				VM_OBJECT_WUNLOCK(obj);
 			}
 			error = VOP_FSYNC(vp, MNT_WAIT, td);
 			if (error != 0) {