Re: [BUG] portïbelong to a lacp aggregate groupïcannot be unselected while the connected port failed

From: zhou zhengwu
Date: Fri Feb 10 2017 - 01:56:43 EST

ad_rx_machine() -> __update_selected(), this funcition will check if any lacp parameter is different. If any change happened, related port will be unselected.

However, this function will not check the changing of port state, for example, whether partner port's port state is synchronization, which will make lacp state machine fail.

On 2017/2/9 17:19, zhou zhengwu wrote:

[1] Testing OS: SUSE 11SP3( kernel version 3.0.93)

[2]Problem description:
ServerA [bond] ----------- [bond] ServerB
Two servers are connected with bonding interfaces LACP is enabled.
Firstly, it works well.
Then, one port (for example, port B) in serverB failed, it can send
but not receive packets including the LACPDU however the port status is
still UP.
In serverB, port B is unselected and traffic is sent through other
aggregate port.
While In serverA, port A connecting with port B of serverB is still
selected by LACP and traffic is still sent through it

[3]Two question about the implementation of LACP RX machine:
1. Following judging condition marked with â*â is reasonable?

static void ad_rx_machine(struct lacpdu *lacpdu, struct port *port)
// detect loopback situation
(!MAC_ADDRESS_COMPARE(&(lacpdu->actor_system), &(port->actor_system))) {
pr_err("%s: An illegal loopback
occurred on adapter (%s).\n"
"Check the configuration to
verify that all adapters are connected to 802.3ad compliant switch

port->slave->dev->master->name, port->slave->dev->name);
__update_selected(lacpdu, port);
__update_ntt(lacpdu, port);
__record_pdu(lacpdu, port);
port->sm_rx_timer_counter =
(u16)(port->actor_oper_port_state & AD_STATE_LACP_TIMEOUT));
port->actor_oper_port_state &=
// verify that if the aggregator is enabled,
the port is enabled too.
//(because if the link goes down for a short
time, the 802.3ad will not
// catch it, and the port will continue to
be disabled)
***** if (port->aggregator
***** && port->aggregator->is_active
***** && !__port_is_enabled(port))
***** __enable_port(port); --------------------
is the judging condition reasonable?

2. While lacp rx machine receive the lacpdu packets, whether the port
should be selected or not should be done. Currently,if lacp rx machine
is in AD_RX_CURRENT and if the partner's configuration is unchanged,
port will still be selected. However, it is not reasonable in some
conditions. For example, partner port failed which can send but not
receive pkts. At the same time, the port still be UP.

static void __update_selected(struct lacpdu *lacpdu, struct port *port)
if (lacpdu && port) {
const struct port_params *partner = &port->partner_oper;

// check if any parameter is different
if (ntohs(lacpdu->actor_port) != partner->port_number ||
ntohs(lacpdu->actor_port_priority) != partner->port_priority ||
MAC_ADDRESS_COMPARE(&lacpdu->actor_system, &partner->system) ||
ntohs(lacpdu->actor_system_priority) !=
partner->system_priority ||
ntohs(lacpdu->actor_key) != partner->key ||
(lacpdu->actor_state & AD_STATE_AGGREGATION) !=
(partner->port_state & AD_STATE_AGGREGATION)) {
// update the state machine Selected variable
port->sm_vars &= ~AD_PORT_SELECTED;