[PATCHv2 net-next 1/3] bonding: set AD_RX_PORT_DISABLED when disabling a port

[Hangbin Liu]

When disabling a port’s collecting and distributing states, updating only
rx_disabled is not sufficient. We also need to set AD_RX_PORT_DISABLED
so that the rx_machine transitions into the AD_RX_EXPIRED state.

One example is in ad_agg_selection_logic(): when a new aggregator is
selected and old active aggregator is disabled, if AD_RX_PORT_DISABLED is
not set, the disabled port may remain stuck in AD_RX_CURRENT due to
continuing to receive partner LACP messages.

The __disable_port() called by ad_disable_collecting_distributing()
does not have this issue, since its caller also clears the
collecting/distributing bits.

The __disable_port() called by bond_3ad_bind_slave() should also be fine,
as the RX state machine is re-initialized to AD_RX_INITIALIZE.

Let's fix this only in ad_agg_selection_logic() to reduce the chances of
unintended side effects.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Hangbin Liu <liuhang...@gmail.com>
---
 drivers/net/bonding/bond_3ad.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/bonding/bond_3ad.c b/drivers/net/bonding/bond_3ad.c
index 1a8de2bf8655..bcf9833e5436 100644
--- a/drivers/net/bonding/bond_3ad.c
+++ b/drivers/net/bonding/bond_3ad.c
@@ -1926,6 +1926,7 @@ static void ad_agg_selection_logic(struct aggregator *agg,
                if (active) {
                        for (port = active->lag_ports; port;
                             port = port->next_port_in_aggregator) {
+                               port->sm_rx_state = AD_RX_PORT_DISABLED;
                                __disable_port(port);
                        }
                }
-- 
2.50.1