From 2cde6acd49daca58b96f1fbc697492825511ad31 Mon Sep 17 00:00:00 2001 From: Neil Horman Date: Mon, 11 Feb 2013 10:25:30 +0000 Subject: netpoll: Fix __netpoll_rcu_free so that it can hold the rtnl lock __netpoll_rcu_free is used to free netpoll structures when the rtnl_lock is already held. The mechanism is used to asynchronously call __netpoll_cleanup outside of the holding of the rtnl_lock, so as to avoid deadlock. Unfortunately, __netpoll_cleanup modifies pointers (dev->np), which means the rtnl_lock must be held while calling it. Further, it cannot be held, because rcu callbacks may be issued in softirq contexts, which cannot sleep. Fix this by converting the rcu callback to a work queue that is guaranteed to get scheduled in process context, so that we can hold the rtnl properly while calling __netpoll_cleanup Tested successfully by myself. Signed-off-by: Neil Horman CC: "David S. Miller" CC: Cong Wang CC: Eric Dumazet Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/net/bonding') diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 22399374b1e1..94c1534dd578 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1249,7 +1249,7 @@ static inline void slave_disable_netpoll(struct slave *slave) return; slave->np = NULL; - __netpoll_free_rcu(np); + __netpoll_free_async(np); } static inline bool slave_dev_support_netpoll(struct net_device *slave_dev) { -- cgit v1.2.3-58-ga151