[PATCHv3 net 0/3] bonding: fix 802.3ad churn machine and port state issues

From: Hangbin Liu

Date: Thu Feb 26 2026 - 07:54:30 EST


This series fixes two issues in the bonding 802.3ad implementation
related to port state management and churn detection:

1. When disabling a port, we need to set AD_RX_PORT_DISABLED to ensure
proper state machine transitions, preventing ports from getting stuck
in AD_RX_CURRENT state.

2. The ad_churn_machine implementation is restructured to follow IEEE
802.1AX-2014 specifications correctly. The current implementation has
several issues: it doesn't transition to "none" state immediately when
synchronization is achieved, and can get stuck in churned state in
multi-aggregator scenarios.

3. Selftests are enhanced to validate both mux state machine and churn
state logic under aggregator selection and failover scenarios.

These changes ensure proper LACP state machine behavior and fix issues
where ports could remain in incorrect states during aggregator failover.

v3: re-post to net, no code change (Jakub)
v2:
* set AD_RX_PORT_DISABLED only in ad_agg_selection_logic to avoid side effect. (Paolo Abeni)
* remove actor_churn as it can only be true when the state is ACTOR_CHURN (Paolo Abeni)
* remove AD_PORT_CHURNED since we don't need it anywhere (Paolo Abeni)
* I didn't add new helper for ad_churn_machine() as it looks not help much.
* https://lore.kernel.org/netdev/20260114064921.57686-1-liuhangbin@xxxxxxxxx
v1: https://lore.kernel.org/netdev/20251124043310.34073-1-liuhangbin@xxxxxxxxx

Hangbin Liu (3):
bonding: set AD_RX_PORT_DISABLED when disabling a port
bonding: restructure ad_churn_machine
selftests: bonding: add mux and churn state testing

drivers/net/bonding/bond_3ad.c | 97 ++++++++++++++-----
.../selftests/drivers/net/bonding/Makefile | 2 +-
...nd_lacp_prio.sh => bond_lacp_ad_select.sh} | 73 ++++++++++++++
3 files changed, 146 insertions(+), 26 deletions(-)
rename tools/testing/selftests/drivers/net/bonding/{bond_lacp_prio.sh => bond_lacp_ad_select.sh} (64%)

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2.50.1