diff --git a/sys/adosfs/advfsops.c b/sys/adosfs/advfsops.c
index 5ecb53421034..738a14b83522 100644
--- a/sys/adosfs/advfsops.c
+++ b/sys/adosfs/advfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: advfsops.c,v 1.38 1999/10/18 19:52:24 wrstuden Exp $	*/
+/*	$NetBSD: advfsops.c,v 1.39 1999/10/20 14:32:09 enami Exp $	*/
 
 /*
  * Copyright (c) 1994 Christian E. Hopps
@@ -300,7 +300,8 @@ adosfs_unmount(mp, mntflags, p)
 	if ((error = vflush(mp, NULLVP, flags)) != 0)
 		return (error);
 	amp = VFSTOADOSFS(mp);
-	amp->devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (amp->devvp->v_type != VBAD)
+		amp->devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(amp->devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(amp->devvp, FREAD, NOCRED, p);
 	vput(amp->devvp);
diff --git a/sys/filecorefs/filecore_vfsops.c b/sys/filecorefs/filecore_vfsops.c
index 992b748e6084..4c6f16a61d5b 100644
--- a/sys/filecorefs/filecore_vfsops.c
+++ b/sys/filecorefs/filecore_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: filecore_vfsops.c,v 1.8 1999/10/16 23:53:27 wrstuden Exp $	*/
+/*	$NetBSD: filecore_vfsops.c,v 1.9 1999/10/20 14:32:10 enami Exp $	*/
 
 /*-
  * Copyright (c) 1998 Andrew McMurry
@@ -393,7 +393,8 @@ filecore_unmount(mp, mntflags, p)
 
 	fcmp = VFSTOFILECORE(mp);
 
-	fcmp->fc_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (fcmp->fc_devvp->v_type != VBAD)
+		fcmp->fc_devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(fcmp->fc_devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(fcmp->fc_devvp, FREAD, NOCRED, p);
 	vput(fcmp->fc_devvp);
diff --git a/sys/isofs/cd9660/cd9660_vfsops.c b/sys/isofs/cd9660/cd9660_vfsops.c
index 2973ecf61c37..15fdff58992d 100644
--- a/sys/isofs/cd9660/cd9660_vfsops.c
+++ b/sys/isofs/cd9660/cd9660_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: cd9660_vfsops.c,v 1.40 1999/10/16 23:53:27 wrstuden Exp $	*/
+/*	$NetBSD: cd9660_vfsops.c,v 1.41 1999/10/20 14:32:10 enami Exp $	*/
 
 /*-
  * Copyright (c) 1994
@@ -510,7 +510,8 @@ cd9660_unmount(mp, mntflags, p)
 		iso_dunmap(isomp->im_dev);
 #endif
 	
-	isomp->im_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (isomp->im_devvp->v_type != VBAD)
+		isomp->im_devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(isomp->im_devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(isomp->im_devvp, FREAD, NOCRED, p);
 	vput(isomp->im_devvp);
diff --git a/sys/msdosfs/msdosfs_vfsops.c b/sys/msdosfs/msdosfs_vfsops.c
index dfd363891c72..7e7a340f5433 100644
--- a/sys/msdosfs/msdosfs_vfsops.c
+++ b/sys/msdosfs/msdosfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: msdosfs_vfsops.c,v 1.63 1999/10/16 23:53:28 wrstuden Exp $	*/
+/*	$NetBSD: msdosfs_vfsops.c,v 1.64 1999/10/20 14:32:10 enami Exp $	*/
 
 /*-
  * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank.
@@ -756,7 +756,8 @@ msdosfs_unmount(mp, mntflags, p)
 	if ((error = vflush(mp, NULLVP, flags)) != 0)
 		return (error);
 	pmp = VFSTOMSDOSFS(mp);
-	pmp->pm_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (pmp->pm_devvp->v_type != VBAD)
+		pmp->pm_devvp->v_specflags &= ~SI_MOUNTEDON;
 #ifdef MSDOSFS_DEBUG
 	{
 		struct vnode *vp = pmp->pm_devvp;
diff --git a/sys/ntfs/ntfs_vfsops.c b/sys/ntfs/ntfs_vfsops.c
index 1a3bc99bed95..beab4b166b86 100644
--- a/sys/ntfs/ntfs_vfsops.c
+++ b/sys/ntfs/ntfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ntfs_vfsops.c,v 1.19 1999/10/20 14:25:42 enami Exp $	*/
+/*	$NetBSD: ntfs_vfsops.c,v 1.20 1999/10/20 14:32:10 enami Exp $	*/
 
 /*-
  * Copyright (c) 1998, 1999 Semen Ustimenko
@@ -670,7 +670,8 @@ ntfs_unmount(
 	vnode_pager_uncache(ntmp->ntm_devvp);
 	VOP_UNLOCK(ntmp->ntm_devvp);
 #else
-	ntmp->ntm_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (ntmp->ntm_devvp->v_type != VBAD)
+		ntmp->ntm_devvp->v_specflags &= ~SI_MOUNTEDON;
 #endif
 
 	vinvalbuf(ntmp->ntm_devvp, V_SAVE, NOCRED, p, 0, 0);
diff --git a/sys/ufs/ext2fs/ext2fs_vfsops.c b/sys/ufs/ext2fs/ext2fs_vfsops.c
index b95be1266d0d..8ea549ce9893 100644
--- a/sys/ufs/ext2fs/ext2fs_vfsops.c
+++ b/sys/ufs/ext2fs/ext2fs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ext2fs_vfsops.c,v 1.28 1999/10/16 23:53:28 wrstuden Exp $	*/
+/*	$NetBSD: ext2fs_vfsops.c,v 1.29 1999/10/20 14:32:11 enami Exp $	*/
 
 /*
  * Copyright (c) 1997 Manuel Bouyer.
@@ -649,7 +649,8 @@ ext2fs_unmount(mp, mntflags, p)
 		fs->e2fs.e2fs_state = E2FS_ISCLEAN;
 		(void) ext2fs_sbupdate(ump, MNT_WAIT);
 	}
-	ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (ump->um_devvp->v_type != VBAD)
+		ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(ump->um_devvp, fs->e2fs_ronly ? FREAD : FREAD|FWRITE,
 		NOCRED, p);
diff --git a/sys/ufs/ffs/ffs_vfsops.c b/sys/ufs/ffs/ffs_vfsops.c
index 0b0a8ffb2dc0..3892763880d2 100644
--- a/sys/ufs/ffs/ffs_vfsops.c
+++ b/sys/ufs/ffs/ffs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: ffs_vfsops.c,v 1.53 1999/10/16 23:53:29 wrstuden Exp $	*/
+/*	$NetBSD: ffs_vfsops.c,v 1.54 1999/10/20 14:32:11 enami Exp $	*/
 
 /*
  * Copyright (c) 1989, 1991, 1993, 1994
@@ -692,7 +692,8 @@ ffs_unmount(mp, mntflags, p)
 		fs->fs_clean = FS_ISCLEAN;
 		(void) ffs_sbupdate(ump, MNT_WAIT);
 	}
-	ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (ump->um_devvp->v_type != VBAD)
+		ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(ump->um_devvp, fs->fs_ronly ? FREAD : FREAD|FWRITE,
 		NOCRED, p);
diff --git a/sys/ufs/lfs/lfs_vfsops.c b/sys/ufs/lfs/lfs_vfsops.c
index d0b54b870552..da25fac4df4e 100644
--- a/sys/ufs/lfs/lfs_vfsops.c
+++ b/sys/ufs/lfs/lfs_vfsops.c
@@ -1,4 +1,4 @@
-/*	$NetBSD: lfs_vfsops.c,v 1.39 1999/10/18 19:52:25 wrstuden Exp $	*/
+/*	$NetBSD: lfs_vfsops.c,v 1.40 1999/10/20 14:32:11 enami Exp $	*/
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -527,7 +527,8 @@ lfs_unmount(mp, mntflags, p)
 	vgone(fs->lfs_ivnode);
 
 	ronly = !fs->lfs_ronly;
-	ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
+	if (ump->um_devvp->v_type != VBAD)
+		ump->um_devvp->v_specflags &= ~SI_MOUNTEDON;
 	vn_lock(ump->um_devvp, LK_EXCLUSIVE | LK_RETRY);
 	error = VOP_CLOSE(ump->um_devvp,
 	    ronly ? FREAD : FREAD|FWRITE, NOCRED, p);