diff --git a/sys/kern/init_main.c b/sys/kern/init_main.c
index 913f777b4526..941faf648531 100644
--- a/sys/kern/init_main.c
+++ b/sys/kern/init_main.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: init_main.c,v 1.73 1995/01/12 05:22:18 cgd Exp $	*/
+/*	$NetBSD: init_main.c,v 1.74 1995/01/18 06:14:43 mycroft Exp $	*/
 
 /*
  * Copyright (c) 1982, 1986, 1989, 1991, 1992, 1993
@@ -263,10 +263,11 @@ main(framep)
 	/* Mount the root file system. */
 	if ((*mountroot)())
 		panic("cannot mount root");
-	mountlist.tqh_first->mnt_op->vfs_refcount++;
+	mountlist.cqh_first->mnt_flag |= MNT_ROOTFS;
+	mountlist.cqh_first->mnt_op->vfs_refcount++;
 
 	/* Get the vnode for '/'.  Set fdp->fd_fd.fd_cdir to reference it. */
-	if (VFS_ROOT(mountlist.tqh_first, &rootvnode))
+	if (VFS_ROOT(mountlist.cqh_first, &rootvnode))
 		panic("cannot find root vnode");
 	fdp->fd_fd.fd_cdir = rootvnode;
 	VREF(fdp->fd_fd.fd_cdir);
diff --git a/sys/kern/vfs_syscalls.c b/sys/kern/vfs_syscalls.c
index dff14453f11e..ecc52a8ec38c 100644
--- a/sys/kern/vfs_syscalls.c
+++ b/sys/kern/vfs_syscalls.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: vfs_syscalls.c,v 1.46 1994/12/15 19:46:08 mycroft Exp $	*/
+/*	$NetBSD: vfs_syscalls.c,v 1.47 1995/01/18 06:14:45 mycroft Exp $	*/
 
 /*
  * Copyright (c) 1989, 1993
@@ -242,7 +242,7 @@ update:
 	 */
 	cache_purge(vp);
 	if (!error) {
-		TAILQ_INSERT_TAIL(&mountlist, mp, mnt_list);
+		CIRCLEQ_INSERT_TAIL(&mountlist, mp, mnt_list);
 		checkdirs(vp);
 		VOP_UNLOCK(vp);
 		vfs_unlock(mp);
@@ -332,6 +332,14 @@ unmount(p, uap, retval)
 		return (error);
 	}
 
+	/*
+	 * Don't allow unmounting the root file system.
+	 */
+	if (mp->mnt_flag & MNT_ROOTFS) {
+		vput(vp);
+		return (EINVAL);
+	}
+
 	/*
 	 * Must be the root of the filesystem
 	 */
@@ -372,9 +380,11 @@ dounmount(mp, flags, p)
 	if (error) {
 		vfs_unlock(mp);
 	} else {
-		vrele(coveredvp);
-		TAILQ_REMOVE(&mountlist, mp, mnt_list);
-		mp->mnt_vnodecovered->v_mountedhere = (struct mount *)0;
+		CIRCLEQ_REMOVE(&mountlist, mp, mnt_list);
+		if (coveredvp != NULLVP) {
+			vrele(coveredvp);
+			coveredvp->v_mountedhere = (struct mount *)0;
+		}
 		mp->mnt_op->vfs_refcount--;
 		vfs_unlock(mp);
 		if (mp->mnt_vnodelist.lh_first != NULL)
@@ -401,12 +411,12 @@ sync(p, uap, retval)
 	register struct mount *mp, *nmp;
 	int asyncflag;
 
-	for (mp = mountlist.tqh_first; mp != NULL; mp = nmp) {
+	for (mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) {
 		/*
 		 * Get the next pointer in case we hang on vfs_busy
 		 * while we are being unmounted.
 		 */
-		nmp = mp->mnt_list.tqe_next;
+		nmp = mp->mnt_list.cqe_next;
 		/*
 		 * The lock check below is to avoid races with mount
 		 * and unmount.
@@ -422,7 +432,7 @@ sync(p, uap, retval)
 			 * Get the next pointer again, as the next filesystem
 			 * might have been unmounted while we were sync'ing.
 			 */
-			nmp = mp->mnt_list.tqe_next;
+			nmp = mp->mnt_list.cqe_next;
 			vfs_unbusy(mp);
 		}
 	}
@@ -535,8 +545,9 @@ getfsstat(p, uap, retval)
 
 	maxcount = SCARG(uap, bufsize) / sizeof(struct statfs);
 	sfsp = (caddr_t)SCARG(uap, buf);
-	for (count = 0, mp = mountlist.tqh_first; mp != NULL; mp = nmp) {
-		nmp = mp->mnt_list.tqe_next;
+	for (count = 0,
+	     mp = mountlist.cqh_first; mp != (void *)&mountlist; mp = nmp) {
+		nmp = mp->mnt_list.cqe_next;
 		if (sfsp && count < maxcount &&
 		    ((mp->mnt_flag & MNT_MLOCK) == 0)) {
 			sp = &mp->mnt_stat;