diff mbox

ipv6: addrconf: Avoid addrconf_disable_change() using RCU read-side lock

Message ID 1484814381-61150-1-git-send-email-wangkefeng.wang@huawei.com
State Accepted
Commit 03e4deff4987f79c34112c5ba4eb195d4f9382b0
Headers show

Commit Message

Kefeng Wang Jan. 19, 2017, 8:26 a.m. UTC
Just like commit 4acd4945cd1e ("ipv6: addrconf: Avoid calling
netdevice notifiers with RCU read-side lock"), it is unnecessary
to make addrconf_disable_change() use RCU iteration over the
netdev list, since it already holds the RTNL lock, or we may meet
Illegal context switch in RCU read-side critical section.

Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>

---
 net/ipv6/addrconf.c | 4 +---
 1 file changed, 1 insertion(+), 3 deletions(-)

-- 
1.7.12.4

Comments

David Miller Jan. 19, 2017, 4:09 p.m. UTC | #1
From: Kefeng Wang <wangkefeng.wang@huawei.com>

Date: Thu, 19 Jan 2017 16:26:21 +0800

> Just like commit 4acd4945cd1e ("ipv6: addrconf: Avoid calling

> netdevice notifiers with RCU read-side lock"), it is unnecessary

> to make addrconf_disable_change() use RCU iteration over the

> netdev list, since it already holds the RTNL lock, or we may meet

> Illegal context switch in RCU read-side critical section.

> 

> Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>


Applied and queued up for -stable, thanks.
diff mbox

Patch

diff --git a/net/ipv6/addrconf.c b/net/ipv6/addrconf.c
index c1e124b..f60e88e 100644
--- a/net/ipv6/addrconf.c
+++ b/net/ipv6/addrconf.c
@@ -5540,8 +5540,7 @@  static void addrconf_disable_change(struct net *net, __s32 newf)
 	struct net_device *dev;
 	struct inet6_dev *idev;
 
-	rcu_read_lock();
-	for_each_netdev_rcu(net, dev) {
+	for_each_netdev(net, dev) {
 		idev = __in6_dev_get(dev);
 		if (idev) {
 			int changed = (!idev->cnf.disable_ipv6) ^ (!newf);
@@ -5550,7 +5549,6 @@  static void addrconf_disable_change(struct net *net, __s32 newf)
 				dev_disable_change(idev);
 		}
 	}
-	rcu_read_unlock();
 }
 
 static int addrconf_disable_ipv6(struct ctl_table *table, int *p, int newf)