Module Name: src
Committed By: riastradh
Date: Mon Mar 20 00:30:03 UTC 2017
Modified Files:
src/sys/kern: subr_autoconf.c
Log Message:
Make sure we hold alldevs_mtx for access to alldevs in deviter.
- Extend alldevs_mtx section in deviter_init.
- Assert ownership of alldevs_mtx in private functions:
. deviter_reinit
. deviter_next1
. deviter_next2
- Acquire alldevs_mtx in deviter_next.
(alldevs_mtx is not relevant to the struct deviter object, which is
private to the caller who must guarantee exclusive access to it.)
To generate a diff of this commit:
cvs rdiff -u -r1.247 -r1.248 src/sys/kern/subr_autoconf.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_autoconf.c
diff -u src/sys/kern/subr_autoconf.c:1.247 src/sys/kern/subr_autoconf.c:1.248
--- src/sys/kern/subr_autoconf.c:1.247 Tue Jul 19 07:44:03 2016
+++ src/sys/kern/subr_autoconf.c Mon Mar 20 00:30:03 2017
@@ -1,4 +1,4 @@
-/* $NetBSD: subr_autoconf.c,v 1.247 2016/07/19 07:44:03 msaitoh Exp $ */
+/* $NetBSD: subr_autoconf.c,v 1.248 2017/03/20 00:30:03 riastradh Exp $ */
/*
* Copyright (c) 1996, 2000 Christopher G. Demetriou
@@ -77,7 +77,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.247 2016/07/19 07:44:03 msaitoh Exp $");
+__KERNEL_RCSID(0, "$NetBSD: subr_autoconf.c,v 1.248 2017/03/20 00:30:03 riastradh Exp $");
#ifdef _KERNEL_OPT
#include "opt_ddb.h"
@@ -2781,17 +2781,15 @@ deviter_init(deviter_t *di, deviter_flag
memset(di, 0, sizeof(*di));
- mutex_enter(&alldevs_mtx);
if ((flags & DEVITER_F_SHUTDOWN) != 0)
flags |= DEVITER_F_RW;
+ mutex_enter(&alldevs_mtx);
if ((flags & DEVITER_F_RW) != 0)
alldevs_nwrite++;
else
alldevs_nread++;
di->di_gen = alldevs_gen++;
- mutex_exit(&alldevs_mtx);
-
di->di_flags = flags;
switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
@@ -2814,11 +2812,14 @@ deviter_init(deviter_t *di, deviter_flag
}
deviter_reinit(di);
+ mutex_exit(&alldevs_mtx);
}
static void
deviter_reinit(deviter_t *di)
{
+
+ KASSERT(mutex_owned(&alldevs_mtx));
if ((di->di_flags & DEVITER_F_RW) != 0)
di->di_prev = TAILQ_LAST(&alldevs, devicelist);
else
@@ -2828,6 +2829,7 @@ deviter_reinit(deviter_t *di)
device_t
deviter_first(deviter_t *di, deviter_flags_t flags)
{
+
deviter_init(di, flags);
return deviter_next(di);
}
@@ -2837,6 +2839,8 @@ deviter_next2(deviter_t *di)
{
device_t dv;
+ KASSERT(mutex_owned(&alldevs_mtx));
+
dv = di->di_prev;
if (dv == NULL)
@@ -2855,6 +2859,8 @@ deviter_next1(deviter_t *di)
{
device_t dv;
+ KASSERT(mutex_owned(&alldevs_mtx));
+
do {
dv = deviter_next2(di);
} while (dv != NULL && !deviter_visits(di, dv));
@@ -2867,9 +2873,11 @@ deviter_next(deviter_t *di)
{
device_t dv = NULL;
+ mutex_enter(&alldevs_mtx);
switch (di->di_flags & (DEVITER_F_LEAVES_FIRST|DEVITER_F_ROOT_FIRST)) {
case 0:
- return deviter_next1(di);
+ dv = deviter_next1(di);
+ break;
case DEVITER_F_LEAVES_FIRST:
while (di->di_curdepth >= 0) {
if ((dv = deviter_next1(di)) == NULL) {
@@ -2878,7 +2886,7 @@ deviter_next(deviter_t *di)
} else if (dv->dv_depth == di->di_curdepth)
break;
}
- return dv;
+ break;
case DEVITER_F_ROOT_FIRST:
while (di->di_curdepth <= di->di_maxdepth) {
if ((dv = deviter_next1(di)) == NULL) {
@@ -2887,10 +2895,13 @@ deviter_next(deviter_t *di)
} else if (dv->dv_depth == di->di_curdepth)
break;
}
- return dv;
+ break;
default:
- return NULL;
+ break;
}
+ mutex_exit(&alldevs_mtx);
+
+ return dv;
}
void
