diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 06cc8d831ebb..da1b843845f8 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -503,7 +503,7 @@ start_init(void *dummy)
 	td = curthread;
 	p = td->td_proc;
 
-	vfs_mountroot(NULL);
+	vfs_mountroot();
 
 	/* Get the vnode for '/'.  Set p->p_fd->fd_cdir to reference it. */
 	if (VFS_ROOT(TAILQ_FIRST(&mountlist), &rootvnode))
diff --git a/sys/kern/vfs_mount.c b/sys/kern/vfs_mount.c
index 404939bee4bd..ce50ef586a9a 100644
--- a/sys/kern/vfs_mount.c
+++ b/sys/kern/vfs_mount.c
@@ -1219,7 +1219,7 @@ dounmount(mp, flags, td)
  * Find and mount the root filesystem
  */
 void
-vfs_mountroot(void *foo __unused)
+vfs_mountroot(void)
 {
 	char		*cp;
 	int		i, error;
diff --git a/sys/sys/mount.h b/sys/sys/mount.h
index 43eb8473d515..0fc937567666 100644
--- a/sys/sys/mount.h
+++ b/sys/sys/mount.h
@@ -456,7 +456,7 @@ dev_t	vfs_getrootfsid(struct mount *);
 struct	mount *vfs_getvfs(fsid_t *);      /* return vfs given fsid */
 int	vfs_modevent(module_t, int, void *);
 int	vfs_mountedon(struct vnode *);    /* is a vfs mounted on vp */
-void	vfs_mountroot(void *);    /* mount our root filesystem */
+void	vfs_mountroot(void);			/* mount our root filesystem */
 int	vfs_rootmountalloc(char *, char *, struct mount **);
 void	vfs_unbusy(struct mount *, struct thread *td);
 void	vfs_unmountall(void);