diff --git a/sys/dev/fdc/fdc.c b/sys/dev/fdc/fdc.c
index 7b894a035d18..597d2daf4543 100644
--- a/sys/dev/fdc/fdc.c
+++ b/sys/dev/fdc/fdc.c
@@ -47,7 +47,7 @@
  * SUCH DAMAGE.
  *
  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
- *	$Id: fd.c,v 1.147 1999/06/26 02:46:52 mckusick Exp $
+ *	$Id: fd.c,v 1.148 1999/07/04 14:58:32 phk Exp $
  *
  */
 
@@ -2127,6 +2127,9 @@ retrier(struct fdc_data *fdc)
 	fail:
 		{
 			dev_t sav_b_dev = bp->b_dev;
+
+			if (fdc->fd == 0)
+				goto bogus;
 			/* Trick diskerr */
 			bp->b_dev = makedev(major(bp->b_dev),
 				    (FDUNIT(minor(bp->b_dev))<<3)|RAW_PART);
@@ -2160,6 +2163,7 @@ retrier(struct fdc_data *fdc)
 								 DEVSTAT_WRITE);
 		fdc->fd->skip = 0;
 		biodone(bp);
+	bogus:
 		fdc->state = FINDWORK;
 		fdc->flags |= FDC_NEEDS_RESET;
 		fdc->fd = (fd_p) 0;
diff --git a/sys/isa/fd.c b/sys/isa/fd.c
index 7b894a035d18..597d2daf4543 100644
--- a/sys/isa/fd.c
+++ b/sys/isa/fd.c
@@ -47,7 +47,7 @@
  * SUCH DAMAGE.
  *
  *	from:	@(#)fd.c	7.4 (Berkeley) 5/25/91
- *	$Id: fd.c,v 1.147 1999/06/26 02:46:52 mckusick Exp $
+ *	$Id: fd.c,v 1.148 1999/07/04 14:58:32 phk Exp $
  *
  */
 
@@ -2127,6 +2127,9 @@ retrier(struct fdc_data *fdc)
 	fail:
 		{
 			dev_t sav_b_dev = bp->b_dev;
+
+			if (fdc->fd == 0)
+				goto bogus;
 			/* Trick diskerr */
 			bp->b_dev = makedev(major(bp->b_dev),
 				    (FDUNIT(minor(bp->b_dev))<<3)|RAW_PART);
@@ -2160,6 +2163,7 @@ retrier(struct fdc_data *fdc)
 								 DEVSTAT_WRITE);
 		fdc->fd->skip = 0;
 		biodone(bp);
+	bogus:
 		fdc->state = FINDWORK;
 		fdc->flags |= FDC_NEEDS_RESET;
 		fdc->fd = (fd_p) 0;