From 7d26bb103c4162003bfdf1d63aaa32b548ad0e9a Mon Sep 17 00:00:00 2001 From: Weiping Pan Date: Tue, 27 Mar 2012 19:18:24 +0000 Subject: [PATCH] bonding: emit event when bonding changes MAC When a bonding device is configured with fail_over_mac=active, we expect to see the MAC address of the new active slave as the source MAC address after failover. But we see that the source MAC address is the MAC address of previous active slave. Emit NETDEV_CHANGEADDR event when bonding changes its MAC address, in order to let arp_netdev_event flush neighbour cache and route cache. How to reproduce this bug ? -----------hostB---------------- hostA ----- switch ---|-- eth0--bond0(192.168.100.2/24)| (192.168.100.1/24 \--|-- eth1-/ | -------------------------------- 1 on hostB, modprobe bonding mode=1 miimon=500 fail_over_mac=active downdelay=1000 num_grat_arp=1 ifconfig bond0 192.168.100.2/24 up ifenslave bond0 eth0 ifenslave bond0 eth1 then eth0 is the active slave, and MAC of bond0 is MAC of eth0. 2 on hostA, ping 192.168.100.2 3 on hostB, tcpdump -i bond0 -p icmp -XXX you will see bond0 uses MAC of eth0 as source MAC in icmp reply. 4 on hostB, ifconfig eth0 down tcpdump -i bond0 -p icmp -XXX (just keep it running in step 3) you will see first bond0 uses MAC of eth1 as source MAC in icmp reply, then it will use MAC of eth0 as source MAC. Signed-off-by: Weiping Pan Signed-off-by: Jay Vosburgh Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index b920d829692a..a20b5850e7ce 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -892,9 +892,15 @@ static void bond_do_fail_over_mac(struct bonding *bond, switch (bond->params.fail_over_mac) { case BOND_FOM_ACTIVE: - if (new_active) + if (new_active) { memcpy(bond->dev->dev_addr, new_active->dev->dev_addr, new_active->dev->addr_len); + write_unlock_bh(&bond->curr_slave_lock); + read_unlock(&bond->lock); + call_netdevice_notifiers(NETDEV_CHANGEADDR, bond->dev); + read_lock(&bond->lock); + write_lock_bh(&bond->curr_slave_lock); + } break; case BOND_FOM_FOLLOW: /* -- 2.30.2