4.14-stable review patch. If anyone has any objections, please let me know.
------------------
[ Upstream commit 3b5b3a3331d141e8f2a7aaae3a94dfa1e61ecbe4 ]
Previously when unbinding a slave the 802.3ad implementation only told partner that the port is not suitable for aggregation by setting the port aggregation state from aggregatable to individual. This is not enough. If the physical layer still stays up and we only unbinded this port from the bond there is nothing in the aggregation status alone to prevent the partner from sending traffic towards us. To ensure that the partner doesn't consider this port at all anymore we should also disable collecting and distributing to signal that this actor is going away. Also clear AD_STATE_SYNCHRONIZATION to ensure partner exits collecting + distributing state.
I have tested this behaviour againts Arista EOS switches with mlx5 cards (physical link stays up even when interface is down) and simulated the same situation virtually Linux <-> Linux with two network namespaces running two veth device pairs. In both cases setting aggregation to individual doesn't alone prevent traffic from being to sent towards this port given that the link stays up in partners end. Partner still keeps it's end in collecting + distributing state and continues until timeout is reached. In most cases this means we are losing the traffic partner sends towards our port while we wait for timeout. This is most visible with slow periodic time (LACP rate slow).
Other open source implementations like Open VSwitch and libreswitch, and vendor implementations like Arista EOS, seem to disable collecting + distributing to when doing similar port disabling/detaching/removing change. With this patch kernel implementation would behave the same way and ensure partner doesn't consider our actor viable anymore.
Signed-off-by: Toni Peltonen peltzi@peltzi.fi Signed-off-by: Jay Vosburgh jay.vosburgh@canonical.com Acked-by: Jonathan Toppins jtoppins@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/bonding/bond_3ad.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c index f43fb2f958a5..93dfcef8afc4 100644 --- a/drivers/net/bonding/bond_3ad.c +++ b/drivers/net/bonding/bond_3ad.c @@ -2086,6 +2086,9 @@ void bond_3ad_unbind_slave(struct slave *slave) aggregator->aggregator_identifier);
/* Tell the partner that this port is not suitable for aggregation */ + port->actor_oper_port_state &= ~AD_STATE_SYNCHRONIZATION; + port->actor_oper_port_state &= ~AD_STATE_COLLECTING; + port->actor_oper_port_state &= ~AD_STATE_DISTRIBUTING; port->actor_oper_port_state &= ~AD_STATE_AGGREGATION; __update_lacpdu_from_port(port); ad_lacpdu_send(port);