diff options
| author | Stephen Hemminger <shemminger@osdl.org> | 2006-01-31 17:44:07 -0800 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2006-01-31 17:44:07 -0800 |
| commit | 3f4cfc2d11c9e29709e6f0f3add54039614d847a (patch) | |
| tree | fe3131288787952d95b578f151dbbf20791951b7 /net/bridge | |
| parent | 5d39a795bfa217b5f7637028c83ab5cb291f37bf (diff) | |
[BRIDGE]: Fix device delete race.
This is a simpler fix for the two races in bridge device removal.
The Xen race of delif and notify is managed now by a new deleted flag.
No need for barriers or other locking because of rtnl mutex.
The del_timer_sync()'s are unnecessary, because br_stp_disable_port
delete's the timers, and they will finish running before RCU callback.
Signed-off-by: Stephen Hemminger <shemminger@osdl.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/bridge')
| -rw-r--r-- | net/bridge/br_if.c | 21 | ||||
| -rw-r--r-- | net/bridge/br_private.h | 1 |
2 files changed, 16 insertions, 6 deletions
diff --git a/net/bridge/br_if.c b/net/bridge/br_if.c index ba442883e87..da687c8dc6f 100644 --- a/net/bridge/br_if.c +++ b/net/bridge/br_if.c @@ -104,6 +104,7 @@ static void destroy_nbp(struct net_bridge_port *p) { struct net_device *dev = p->dev; + dev->br_port = NULL; p->br = NULL; p->dev = NULL; dev_put(dev); @@ -118,13 +119,24 @@ static void destroy_nbp_rcu(struct rcu_head *head) destroy_nbp(p); } -/* called with RTNL */ +/* Delete port(interface) from bridge is done in two steps. + * via RCU. First step, marks device as down. That deletes + * all the timers and stops new packets from flowing through. + * + * Final cleanup doesn't occur until after all CPU's finished + * processing packets. + * + * Protected from multiple admin operations by RTNL mutex + */ static void del_nbp(struct net_bridge_port *p) { struct net_bridge *br = p->br; struct net_device *dev = p->dev; - dev->br_port = NULL; + /* Race between RTNL notify and RCU callback */ + if (p->deleted) + return; + dev_set_promiscuity(dev, -1); cancel_delayed_work(&p->carrier_check); @@ -132,16 +144,13 @@ static void del_nbp(struct net_bridge_port *p) spin_lock_bh(&br->lock); br_stp_disable_port(p); + p->deleted = 1; spin_unlock_bh(&br->lock); br_fdb_delete_by_port(br, p); list_del_rcu(&p->list); - del_timer_sync(&p->message_age_timer); - del_timer_sync(&p->forward_delay_timer); - del_timer_sync(&p->hold_timer); - call_rcu(&p->rcu, destroy_nbp_rcu); } diff --git a/net/bridge/br_private.h b/net/bridge/br_private.h index c5bd631ffcd..e330b17b6d8 100644 --- a/net/bridge/br_private.h +++ b/net/bridge/br_private.h @@ -68,6 +68,7 @@ struct net_bridge_port /* STP */ u8 priority; u8 state; + u8 deleted; u16 port_no; unsigned char topology_change_ack; unsigned char config_pending; |