Re: [PATCH net] bonding: force carrier update when releasing slave

From: Jay Vosburgh
Date: Thu Feb 17 2022 - 13:40:46 EST


Zhang Changzhong <zhangchangzhong@xxxxxxxxxx> wrote:

>In __bond_release_one(), bond_set_carrier() is only called when bond
>device has no slave. Therefore, if we remove the up slave from a master
>with two slaves and keep the down slave, the master will remain up.
>
>Fix this by moving bond_set_carrier() out of if (!bond_has_slaves(bond))
>statement.
>
>Reproducer:
>$ insmod bonding.ko mode=0 miimon=100 max_bonds=2
>$ ifconfig bond0 up
>$ ifenslave bond0 eth0 eth1
>$ ifconfig eth0 down
>$ ifenslave -d bond0 eth1
>$ cat /proc/net/bonding/bond0
>
>Fixes: ff59c4563a8d ("[PATCH] bonding: support carrier state for master")
>Signed-off-by: Zhang Changzhong <zhangchangzhong@xxxxxxxxxx>

Acked-by: Jay Vosburgh <jay.vosburgh@xxxxxxxxxxxxx>


>---
> drivers/net/bonding/bond_main.c | 5 ++---
> 1 file changed, 2 insertions(+), 3 deletions(-)
>
>diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
>index 238b56d..aebeb46 100644
>--- a/drivers/net/bonding/bond_main.c
>+++ b/drivers/net/bonding/bond_main.c
>@@ -2379,10 +2379,9 @@ static int __bond_release_one(struct net_device *bond_dev,
> bond_select_active_slave(bond);
> }
>
>- if (!bond_has_slaves(bond)) {
>- bond_set_carrier(bond);
>+ bond_set_carrier(bond);
>+ if (!bond_has_slaves(bond))
> eth_hw_addr_random(bond_dev);
>- }
>
> unblock_netpoll_tx();
> synchronize_rcu();
>--
>2.9.5
>