Commit 70fc6649 authored by Tonghao Zhang's avatar Tonghao Zhang Committed by Paolo Abeni
Browse files

net: bonding: move bond_should_notify_peers, e.g. into rtnl lock block 



This patch tries to avoid the possible peer notify event loss.

In bond_mii_monitor()/bond_activebackup_arp_mon(), when we hold the rtnl lock:
- check send_peer_notif again to avoid unconditionally reducing this value.
- send_peer_notif may have been reset. Therefore, it is necessary to check
  whether to send peer notify via bond_should_notify_peers() to avoid the
  loss of notification events.

Cc: Jay Vosburgh <jv@jvosburgh.net>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Simon Horman <horms@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Andrew Lunn <andrew+netdev@lunn.ch>
Cc: Nikolay Aleksandrov <razor@blackwall.org>
Cc: Hangbin Liu <liuhangbin@gmail.com>
Cc: Jason Xing <kerneljasonxing@gmail.com>
Signed-off-by: default avatarTonghao Zhang <tonghao@bamaicloud.com>
Reviewed-by: default avatarHangbin Liu <liuhangbin@gmail.com>
Link: https://patch.msgid.link/78cef328822b94638c97638b89011c507b8bf19e.1768709239.git.tonghao@bamaicloud.com


Signed-off-by: default avatarPaolo Abeni <pabeni@redhat.com>
parent 11ea9b8a

drivers/net/bonding/bond_main.c

+9 −21
Original line number Diff line number Diff line
@@ -2816,11 +2816,10 @@ static void bond_mii_monitor(struct work_struct *work) 
{

	struct bonding *bond = container_of(work, struct bonding,

					    mii_work.work);

	bool should_notify_peers;

	bool commit;

	unsigned long delay;

	struct slave *slave;

	struct list_head *iter;

	struct slave *slave;

	unsigned long delay;

	bool commit;



	delay = msecs_to_jiffies(bond->params.miimon);
@@ -2829,7 +2828,6 @@ static void bond_mii_monitor(struct work_struct *work) 


	rcu_read_lock();



	should_notify_peers = bond_should_notify_peers(bond);

	commit = !!bond_miimon_inspect(bond);



	rcu_read_unlock();
@@ -2849,12 +2847,8 @@ static void bond_mii_monitor(struct work_struct *work) 
			bond_miimon_commit(bond);

		}



		if (bond->send_peer_notif) {

			bond->send_peer_notif--;

			if (should_notify_peers)

				call_netdevice_notifiers(NETDEV_NOTIFY_PEERS,

							 bond->dev);

		}

		if (bond->send_peer_notif)

			bond_peer_notify_may_events(bond, true);



		rtnl_unlock();	/* might sleep, hold no other locks */

	}
@@ -3765,7 +3759,6 @@ static bool bond_ab_arp_probe(struct bonding *bond) 


static void bond_activebackup_arp_mon(struct bonding *bond)

{

	bool should_notify_peers = false;

	bool should_notify_rtnl = false;

	int delta_in_ticks;
@@ -3776,15 +3769,12 @@ static void bond_activebackup_arp_mon(struct bonding *bond) 


	rcu_read_lock();



	should_notify_peers = bond_should_notify_peers(bond);



	if (bond_ab_arp_inspect(bond)) {

		rcu_read_unlock();



		/* Race avoidance with bond_close flush of workqueue */

		if (!rtnl_trylock()) {

			delta_in_ticks = 1;

			should_notify_peers = false;

			goto re_arm;

		}
@@ -3801,15 +3791,13 @@ static void bond_activebackup_arp_mon(struct bonding *bond) 
	if (bond->params.arp_interval)

		queue_delayed_work(bond->wq, &bond->arp_work, delta_in_ticks);



	if (should_notify_peers || should_notify_rtnl) {

	if (bond->send_peer_notif || should_notify_rtnl) {

		if (!rtnl_trylock())

			return;



		if (should_notify_peers) {

			bond->send_peer_notif--;

			call_netdevice_notifiers(NETDEV_NOTIFY_PEERS,

						 bond->dev);

		}

		if (bond->send_peer_notif)

			bond_peer_notify_may_events(bond, true);



		if (should_notify_rtnl) {

			bond_slave_state_notify(bond);

			bond_slave_link_notify(bond);