Module Name: src
Committed By: buhrow
Date: Mon Feb 13 19:07:14 UTC 2023
Modified Files:
src/sys/kern: subr_devsw.c
Log Message:
When a device driver calls devsw_attach() it has the option of
attaching a block device
structure and a character device structure, or, just the character device
structure.
With the existing code, if a driver elects not to attach a block device
structure and if it
asks for a major number to be dynamically assigned to its character interface,
that driver will not be able to detach and reattach its character driver
interface. This is a very
long standing bug which didn't come to light until we began using loadable
kernel modules more
heavily. this patch fixes this problem. With this patch in place, drivers
that implement only
a character device interface may detach and reattach that character interface
as often as they
need to.
Fixes PR kern/57229
To generate a diff of this commit:
cvs rdiff -u -r1.49 -r1.50 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:1.49 src/sys/kern/subr_devsw.c:1.50
--- src/sys/kern/subr_devsw.c:1.49 Sat Oct 29 10:52:36 2022
+++ src/sys/kern/subr_devsw.c Mon Feb 13 19:07:14 2023
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_devsw.c,v 1.49 2022/10/29 10:52:36 riastradh Exp $ */
+/* $NetBSD: subr_devsw.c,v 1.50 2023/02/13 19:07:14 buhrow 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 1.49 2022/10/29 10:52:36 riastradh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_devsw.c,v 1.50 2023/02/13 19:07:14 buhrow Exp $");
#ifdef _KERNEL_OPT
#include "opt_dtrace.h"
@@ -397,7 +397,7 @@ devsw_attach(const char *devname,
if (conv->d_name == NULL || strcmp(devname, conv->d_name) != 0)
continue;
- if (*bmajor < 0)
+ if ((bdev != NULL) && (*bmajor < 0))
*bmajor = conv->d_bmajor;
if (*cmajor < 0)
*cmajor = conv->d_cmajor;
