--- /usr/src/sys/gnu/fs/xfs/FreeBSD/xfs_vnode.c	2008-07-03 15:17:19.000000000 +0200
+++ src/sys/gnu/fs/xfs/FreeBSD/xfs_vnode.c	2008-07-17 16:26:05.000000000 +0200
@@ -104,13 +104,11 @@
 
 	vp = vmap->v_vp;
 
-	error = vget(vp, 0, curthread);
-	if (error) {
-		vdrop(vp);
+	error = vget(vp, LK_EXCLUSIVE, curthread);
+	vdrop(vp);
+	if (error)
 		return (NULL);
-	}
 
-	vdrop(vp);
 	if (vp->v_data != xfs_vp) {
 		vput(vp);
 		return (NULL);
--- /usr/src/sys/kern/vfs_subr.c	2008-05-31 23:42:15.000000000 +0200
+++ src/sys/kern/vfs_subr.c	2008-07-17 16:28:15.000000000 +0200
@@ -2038,6 +2038,8 @@
 
 	error = 0;
 	VFS_ASSERT_GIANT(vp->v_mount);
+	VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
+	    ("vget: invalid lock operation"));
 	if ((flags & LK_INTERLOCK) == 0)
 		VI_LOCK(vp);
 	vholdl(vp);