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Miller" , Jakub Kicinski , Paolo Abeni Cc: Simon Horman , Andrew Lunn , netdev@vger.kernel.org, eric.dumazet@gmail.com, Eric Dumazet , Tonghao Zhang , Hangbin Liu , Jay Vosburgh Content-Type: text/plain; charset="UTF-8" Commit f1986b3a9f2e ("net: bonding: skip the 2nd trylock when first one fail") changed bond_activebackup_arp_mon() to reschedule arp_work in 1 tick if the second rtnl_trylock() fails (for sending peer/slave notifications). However, by the time bond_activebackup_arp_mon() reaches this second lock check, bond_ab_arp_probe() has already been executed and sent an ARP probe. If RTNL remains contended, rescheduling every 1 tick causes bond_activebackup_arp_mon() to re-execute bond_ab_arp_probe() every jiffy, flooding the network with ARP probes at HZ frequency (e.g. 1000 pkts/sec) instead of respecting the configured arp_interval. If rtnl_trylock() fails at the second check, do not change delta_in_ticks to 1 so that the next ARP monitor execution is scheduled according to the configured arp_interval, matching the behavior in bond_loadbalance_arp_mon(). Fixes: f1986b3a9f2e ("net: bonding: skip the 2nd trylock when first one fail") Signed-off-by: Eric Dumazet --- Cc: Tonghao Zhang Cc: Hangbin Liu Cc: Jay Vosburgh --- drivers/net/bonding/bond_main.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index ef9eb0c53c66..c23cf18a996a 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -3871,10 +3871,8 @@ static void bond_activebackup_arp_mon(struct bonding *bond) rcu_read_unlock(); if (READ_ONCE(bond->send_peer_notif) || should_notify_rtnl) { - if (!rtnl_trylock()) { - delta_in_ticks = 1; + if (!rtnl_trylock()) goto re_arm; - } if (bond->send_peer_notif) bond_peer_notify_may_events(bond, true); -- 2.55.0.897.gb25b4bd76c-goog