diff --git a/sys/gnu/ext2fs/ext2_readwrite.c b/sys/gnu/ext2fs/ext2_readwrite.c
index b49666afe1ba..7efe39afe4a0 100644
--- a/sys/gnu/ext2fs/ext2_readwrite.c
+++ b/sys/gnu/ext2fs/ext2_readwrite.c
@@ -254,7 +254,8 @@ WRITE(ap)
 
 		error =
 		    uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
-		if (ioflag & IO_VMIO)
+		if ((ioflag & IO_VMIO) &&
+		   (LIST_FIRST(&bp->b_dep) == NULL)) /* in ext2fs? */
 			bp->b_flags |= B_RELBUF;
 
 		if (ioflag & IO_SYNC) {
diff --git a/sys/gnu/fs/ext2fs/ext2_readwrite.c b/sys/gnu/fs/ext2fs/ext2_readwrite.c
index b49666afe1ba..7efe39afe4a0 100644
--- a/sys/gnu/fs/ext2fs/ext2_readwrite.c
+++ b/sys/gnu/fs/ext2fs/ext2_readwrite.c
@@ -254,7 +254,8 @@ WRITE(ap)
 
 		error =
 		    uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
-		if (ioflag & IO_VMIO)
+		if ((ioflag & IO_VMIO) &&
+		   (LIST_FIRST(&bp->b_dep) == NULL)) /* in ext2fs? */
 			bp->b_flags |= B_RELBUF;
 
 		if (ioflag & IO_SYNC) {
diff --git a/sys/kern/vfs_bio.c b/sys/kern/vfs_bio.c
index f494f73c1a0e..6f8088311deb 100644
--- a/sys/kern/vfs_bio.c
+++ b/sys/kern/vfs_bio.c
@@ -11,7 +11,7 @@
  * 2. Absolutely no warranty of function or purpose is made by the author
  *		John S. Dyson.
  *
- * $Id: vfs_bio.c,v 1.164 1998/05/01 15:10:59 peter Exp $
+ * $Id: vfs_bio.c,v 1.165 1998/07/04 20:45:31 julian Exp $
  */
 
 /*
@@ -1458,7 +1458,8 @@ getblk(struct vnode * vp, daddr_t blkno, int size, int slpflag, int slptimeo)
 					bp->b_flags |= B_NOCACHE;
 					VOP_BWRITE(bp);
 				} else {
-					if (bp->b_flags & B_VMIO) {
+					if ((bp->b_flags & B_VMIO) &&
+					   (LIST_FIRST(&bp->b_dep) == NULL)) {
 						bp->b_flags |= B_RELBUF;
 						brelse(bp);
 					} else {
@@ -1571,7 +1572,7 @@ geteblk(int size)
 	while ((bp = getnewbuf(0, (daddr_t) 0, 0, 0, size, MAXBSIZE)) == 0);
 	splx(s);
 	allocbuf(bp, size);
-	bp->b_flags |= B_INVAL;
+	bp->b_flags |= B_INVAL; /* b_dep cleared by getnewbuf() */
 	return (bp);
 }
 
diff --git a/sys/ufs/ufs/ufs_readwrite.c b/sys/ufs/ufs/ufs_readwrite.c
index a2e4fd412cfb..b4d50e7b81f3 100644
--- a/sys/ufs/ufs/ufs_readwrite.c
+++ b/sys/ufs/ufs/ufs_readwrite.c
@@ -31,7 +31,7 @@
  * SUCH DAMAGE.
  *
  *	@(#)ufs_readwrite.c	8.11 (Berkeley) 5/8/95
- * $Id: ufs_readwrite.c,v 1.49 1998/04/06 18:18:50 peter Exp $
+ * $Id: ufs_readwrite.c,v 1.50 1998/06/04 17:04:44 dfr Exp $
  */
 
 #define	BLKSIZE(a, b, c)	blksize(a, b, c)
@@ -210,7 +210,8 @@ READ(ap)
 		if (error)
 			break;
 
-		if (ioflag & IO_VMIO) {
+		if ((ioflag & IO_VMIO) &&
+		   (LIST_FIRST(&bp->b_dep) == NULL)) {
 			bp->b_flags |= B_RELBUF;
 			brelse(bp);
 		} else {
@@ -219,7 +220,8 @@ READ(ap)
 	}
 
 	if (bp != NULL) {
-		if (ioflag & IO_VMIO) {
+		if ((ioflag & IO_VMIO) &&
+		   (LIST_FIRST(&bp->b_dep) == NULL)) {
 			bp->b_flags |= B_RELBUF;
 			brelse(bp);
 		} else {
@@ -355,7 +357,8 @@ WRITE(ap)
 
 		error =
 		    uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio);
-		if (ioflag & IO_VMIO)
+		if ((ioflag & IO_VMIO) &&
+		   (LIST_FIRST(&bp->b_dep) == NULL))
 			bp->b_flags |= B_RELBUF;
 
 		if (ioflag & IO_SYNC) {