Module Name: src
Committed By: riastradh
Date: Sat Jul 9 10:30:27 UTC 2022
Modified Files:
src/sys/kern: subr_devsw.c
Log Message:
devsw(9): Forbid extant linked autoconf instances in devsw_detach.
To generate a diff of this commit:
cvs rdiff -u -r1.45 -r1.46 src/sys/kern/subr_devsw.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/kern/subr_devsw.c
diff -u src/sys/kern/subr_devsw.c:1.45 src/sys/kern/subr_devsw.c:1.46
--- src/sys/kern/subr_devsw.c:1.45 Mon Mar 28 12:41:17 2022
+++ src/sys/kern/subr_devsw.c Sat Jul 9 10:30:27 2022
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_devsw.c,v 1.45 2022/03/28 12:41:17 riastradh Exp $ */
+/* $NetBSD: subr_devsw.c,v 1.46 2022/07/09 10:30:27 riastradh Exp $ */
/*-
* Copyright (c) 2001, 2002, 2007, 2008 The NetBSD Foundation, Inc.
@@ -69,7 +69,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_devsw.c,v 1.45 2022/03/28 12:41:17 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_devsw.c,v 1.46 2022/07/09 10:30:27 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_dtrace.h"
@@ -372,10 +372,35 @@ cdevsw_attach(const struct cdevsw *devsw
static void
devsw_detach_locked(const struct bdevsw *bdev, const struct cdevsw *cdev)
{
- int bi, ci = -1/*XXXGCC*/;
+ int bi, ci = -1/*XXXGCC*/, di;
+ struct cfdriver *cd;
+ device_t dv;
KASSERT(mutex_owned(&device_lock));
+ /*
+ * If this is wired to an autoconf device, make sure the device
+ * has no more instances. No locking here because under
+ * correct use of devsw_detach, none of this state can change
+ * at this point.
+ */
+ if (cdev != NULL && (cd = cdev->d_cfdriver) != NULL) {
+ for (di = 0; di < cd->cd_ndevs; di++) {
+ KASSERTMSG((dv = cd->cd_devs[di]) == NULL,
+ "detaching character device driver %s"
+ " still has attached unit %s",
+ cd->cd_name, device_xname(dv));
+ }
+ }
+ if (bdev != NULL && (cd = bdev->d_cfdriver) != NULL) {
+ for (di = 0; di < cd->cd_ndevs; di++) {
+ KASSERTMSG((dv = cd->cd_devs[di]) == NULL,
+ "detaching block device driver %s"
+ " still has attached unit %s",
+ cd->cd_name, device_xname(dv));
+ }
+ }
+
/* Prevent new references. */
if (bdev != NULL) {
for (bi = 0; bi < max_bdevsws; bi++) {
