From 6fde8f037e604e05df1529e4689041715d6d55d2 Mon Sep 17 00:00:00 2001 From: Ding Tianhong Date: Tue, 28 Jan 2014 11:48:53 +0800 Subject: [PATCH] bonding: fix locking in bond_loadbalance_arp_mon() The commit 1d3ee88ae0d605629bf369 (bonding: add netlink attributes to slave link dev) has add rtmsg_ifinfo() in bond_set_active_slave() and bond_set_backup_slave(), so the two function need to called in RTNL lock, but bond_loadbalance_arp_mon() only calling these functions in RCU, warning message will occurs. fix this by add a new function bond_slave_state_change(), which will reset the slave's state after slave link check, so remove the bond_set_xxx_slave() from the cycle and only record the slave_state_changed, this will call the new function to set all slaves to new state in RTNL later. Cc: Jay Vosburgh Cc: Veaceslav Falico Cc: Andy Gospodarek Signed-off-by: Ding Tianhong Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 29 +++++++++++++++++------------ drivers/net/bonding/bonding.h | 13 +++++++++++++ 2 files changed, 30 insertions(+), 12 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index dd75615d85f2..4c08018d7333 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -2346,7 +2346,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work) arp_work.work); struct slave *slave, *oldcurrent; struct list_head *iter; - int do_failover = 0; + int do_failover = 0, slave_state_changed = 0; if (!bond_has_slaves(bond)) goto re_arm; @@ -2370,7 +2370,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work) bond_time_in_interval(bond, slave->dev->last_rx, 1)) { slave->link = BOND_LINK_UP; - bond_set_active_slave(slave); + slave_state_changed = 1; /* primary_slave has no meaning in round-robin * mode. the window of a slave being up and @@ -2399,7 +2399,7 @@ static void bond_loadbalance_arp_mon(struct work_struct *work) !bond_time_in_interval(bond, slave->dev->last_rx, 2)) { slave->link = BOND_LINK_DOWN; - bond_set_backup_slave(slave); + slave_state_changed = 1; if (slave->link_failure_count < UINT_MAX) slave->link_failure_count++; @@ -2426,19 +2426,24 @@ static void bond_loadbalance_arp_mon(struct work_struct *work) rcu_read_unlock(); - if (do_failover) { - /* the bond_select_active_slave must hold RTNL - * and curr_slave_lock for write. - */ + if (do_failover || slave_state_changed) { if (!rtnl_trylock()) goto re_arm; - block_netpoll_tx(); - write_lock_bh(&bond->curr_slave_lock); - bond_select_active_slave(bond); + if (slave_state_changed) { + bond_slave_state_change(bond); + } else if (do_failover) { + /* the bond_select_active_slave must hold RTNL + * and curr_slave_lock for write. + */ + block_netpoll_tx(); + write_lock_bh(&bond->curr_slave_lock); - write_unlock_bh(&bond->curr_slave_lock); - unblock_netpoll_tx(); + bond_select_active_slave(bond); + + write_unlock_bh(&bond->curr_slave_lock); + unblock_netpoll_tx(); + } rtnl_unlock(); } diff --git a/drivers/net/bonding/bonding.h b/drivers/net/bonding/bonding.h index 1a9062f4e0d6..86ccfb9f71cc 100644 --- a/drivers/net/bonding/bonding.h +++ b/drivers/net/bonding/bonding.h @@ -303,6 +303,19 @@ static inline void bond_set_backup_slave(struct slave *slave) } } +static inline void bond_slave_state_change(struct bonding *bond) +{ + struct list_head *iter; + struct slave *tmp; + + bond_for_each_slave(bond, tmp, iter) { + if (tmp->link == BOND_LINK_UP) + bond_set_active_slave(tmp); + else if (tmp->link == BOND_LINK_DOWN) + bond_set_backup_slave(tmp); + } +} + static inline int bond_slave_state(struct slave *slave) { return slave->backup; -- GitLab