[PATCH] ipv6: addrconf: Avoid addrconf_disable_change() using RCU read-side lock
From: Kefeng Wang
Date: Thu Jan 19 2017 - 03:31:44 EST
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@xxxxxxxxxx>
---
net/ipv6/addrconf.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)
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)
--
1.7.12.4