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

From: Zhang Changzhong <zhangchangzhong@huawei.com>
To: Jay Vosburgh <j.vosburgh@gmail.com>,
	Veaceslav Falico <vfalico@gmail.com>,
	Andy Gospodarek <andy@greyhouse.net>,
	"David S. Miller" <davem@davemloft.net>,
	Jakub Kicinski <kuba@kernel.org>, Jeff Garzik <jeff@garzik.org>
Cc: Zhang Changzhong <zhangchangzhong@huawei.com>,
	<netdev@vger.kernel.org>, <linux-kernel@vger.kernel.org>
Subject: [PATCH net] bonding: force carrier update when releasing slave
Date: Wed, 16 Feb 2022 22:18:08 +0800	[thread overview]
Message-ID: <1645021088-38370-1-git-send-email-zhangchangzhong@huawei.com> (raw)

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@huawei.com>
---
 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

