summaryrefslogtreecommitdiffstats
path: root/net/core
diff options
context:
space:
mode:
authorKirill Tkhai <ktkhai@virtuozzo.com>2018-03-30 19:38:27 +0300
committerDavid S. Miller <davem@davemloft.net>2018-03-31 22:24:58 -0400
commitfc1dd36992bb041b4470120aecf8986910c56088 (patch)
tree7fbea89ad406d55660f89abf4f380b7e010b565d /net/core
parentc679f6a26dc3d450b76e94717850a14ff706cc58 (diff)
downloadop-kernel-dev-fc1dd36992bb041b4470120aecf8986910c56088.zip
op-kernel-dev-fc1dd36992bb041b4470120aecf8986910c56088.tar.gz
net: Remove net_rwsem from {, un}register_netdevice_notifier()
These functions take net_rwsem, while wireless_nlevent_flush() also takes it. But down_read() can't be taken recursive, because of rw_semaphore design, which prevents it to be occupied by only readers forever. Since we take pernet_ops_rwsem in {,un}register_netdevice_notifier(), net list can't change, so these down_read()/up_read() can be removed. Fixes: f0b07bb151b0 "net: Introduce net_rwsem to protect net_namespace_list" Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/core')
-rw-r--r--net/core/dev.c5
1 files changed, 0 insertions, 5 deletions
diff --git a/net/core/dev.c b/net/core/dev.c
index 07da7ad..8edb588 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -1633,7 +1633,6 @@ int register_netdevice_notifier(struct notifier_block *nb)
goto unlock;
if (dev_boot_phase)
goto unlock;
- down_read(&net_rwsem);
for_each_net(net) {
for_each_netdev(net, dev) {
err = call_netdevice_notifier(nb, NETDEV_REGISTER, dev);
@@ -1647,7 +1646,6 @@ int register_netdevice_notifier(struct notifier_block *nb)
call_netdevice_notifier(nb, NETDEV_UP, dev);
}
}
- up_read(&net_rwsem);
unlock:
rtnl_unlock();
@@ -1671,7 +1669,6 @@ rollback:
}
outroll:
- up_read(&net_rwsem);
raw_notifier_chain_unregister(&netdev_chain, nb);
goto unlock;
}
@@ -1704,7 +1701,6 @@ int unregister_netdevice_notifier(struct notifier_block *nb)
if (err)
goto unlock;
- down_read(&net_rwsem);
for_each_net(net) {
for_each_netdev(net, dev) {
if (dev->flags & IFF_UP) {
@@ -1715,7 +1711,6 @@ int unregister_netdevice_notifier(struct notifier_block *nb)
call_netdevice_notifier(nb, NETDEV_UNREGISTER, dev);
}
}
- up_read(&net_rwsem);
unlock:
rtnl_unlock();
up_write(&pernet_ops_rwsem);
OpenPOWER on IntegriCloud