diff -Naur linux-2.6.2/drivers/scsi/sg.c linux-2.6.2-cdev_unmap/drivers/scsi/sg.c
--- linux-2.6.2/drivers/scsi/sg.c	Fri Feb  6 14:12:22 2004
+++ linux-2.6.2-cdev_unmap/drivers/scsi/sg.c	Fri Feb  6 14:12:35 2004
@@ -1513,6 +1513,7 @@
 	if (sdp) {
 		sysfs_remove_link(&scsidp->sdev_gendev.kobj, "generic");
 		sysfs_remove_link(&sdp->cdev->kobj, "device");
+		cdev_unmap(MKDEV(SCSI_GENERIC_MAJOR, sdp->disk->first_minor), 1);
 		cdev_del(sdp->cdev);
 		sdp->cdev = NULL;
 		devfs_remove("%s/generic", scsidp->devfs_name);
diff -Naur linux-2.6.2/drivers/scsi/st.c linux-2.6.2-cdev_unmap/drivers/scsi/st.c
--- linux-2.6.2/drivers/scsi/st.c	Fri Jan  9 00:59:45 2004
+++ linux-2.6.2-cdev_unmap/drivers/scsi/st.c	Fri Feb  6 14:18:57 2004
@@ -3964,6 +3964,7 @@
 				for (j=0; j < 2; j++) {
 					sysfs_remove_link(&tpnt->modes[mode].cdevs[j]->kobj,
 							  "device");
+					cdev_unmap(MKDEV(SCSI_TAPE_MAJOR, TAPE_MINOR(i, mode, j)), 1);
 					cdev_del(tpnt->modes[mode].cdevs[j]);
 					tpnt->modes[mode].cdevs[j] = NULL;
 				}