diff --git a/sys/kern/vfs_vnops.c b/sys/kern/vfs_vnops.c
index 70cdcdc6f75..1f2cceaf7a6 100644
--- a/sys/kern/vfs_vnops.c
+++ b/sys/kern/vfs_vnops.c
@@ -351,8 +351,8 @@ vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
 
 	while ((fmode & (O_EXLOCK | O_SHLOCK)) != 0) {
 		KASSERT(fp != NULL, ("open with flock requires fp"));
-		if (fp->f_type != DTYPE_VNODE) {
-			error = EBADF;
+		if (fp->f_type != DTYPE_NONE && fp->f_type != DTYPE_VNODE) {
+			error = EOPNOTSUPP;
 			break;
 		}
 		lock_flags = VOP_ISLOCKED(vp);
diff --git a/sys/sys/file.h b/sys/sys/file.h
index 353c92f365a..c51f26a41d2 100644
--- a/sys/sys/file.h
+++ b/sys/sys/file.h
@@ -53,6 +53,7 @@ struct vnode;
 
 #endif /* _KERNEL */
 
+#define	DTYPE_NONE	0	/* not yet initialized */
 #define	DTYPE_VNODE	1	/* file */
 #define	DTYPE_SOCKET	2	/* communications endpoint */
 #define	DTYPE_PIPE	3	/* pipe */