From: Louis Scalbert Date: Wed, 3 Jun 2026 15:03:28 +0000 (+0200) Subject: bonding: 3ad: add lacp_strict configuration knob X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=32b0b8953343eaceaa816a9ead3b6bb66355c64e;p=thirdparty%2Flinux.git bonding: 3ad: add lacp_strict configuration knob When an 802.3ad (LACP) bonding interface has no slaves in the collecting/distributing state, the bonding master still reports carrier as up as long as at least 'min_links' slaves have carrier. In this situation, only one slave is effectively used for TX/RX, while traffic received on other slaves is dropped. Upper-layer daemons therefore consider the interface operational, even though traffic may be blackholed if the lack of LACP negotiation means the partner is not ready to deal with traffic. Introduce a configuration knob to control this behavior. It allows the bonding master to assert carrier only when at least 'min_links' slaves are in Collecting_Distributing state. The default mode preserves the existing behavior. This patch only introduces the knob; its behavior is implemented in the subsequent commit. Fixes: 655f8919d549 ("bonding: add min links parameter to 802.3ad") Signed-off-by: Louis Scalbert Acked-by: Jay Vosburgh Link: https://patch.msgid.link/20260603150331.1919611-4-louis.scalbert@6wind.com Signed-off-by: Jakub Kicinski --- diff --git a/Documentation/netlink/specs/rt-link.yaml b/Documentation/netlink/specs/rt-link.yaml index 694fd0a3a0c1..892979da098e 100644 --- a/Documentation/netlink/specs/rt-link.yaml +++ b/Documentation/netlink/specs/rt-link.yaml @@ -1356,6 +1356,9 @@ attribute-sets: - name: broadcast-neigh type: u8 + - + name: lacp-strict + type: u8 - name: bond-ad-info-attrs name-prefix: ifla-bond-ad-info- diff --git a/Documentation/networking/bonding.rst b/Documentation/networking/bonding.rst index e700bf1d095c..33ca5afafdf6 100644 --- a/Documentation/networking/bonding.rst +++ b/Documentation/networking/bonding.rst @@ -619,6 +619,29 @@ min_links aggregator cannot be active without at least one available link, setting this option to 0 or to 1 has the exact same effect. +lacp_strict + + Specifies the fallback behavior of a bonding when LACP negotiation + fails on all slave links, i.e. when no slave is in the + Collecting_Distributing state, while at least `min_links` link still + reports carrier up. + + This option is only applicable to 802.3ad mode (mode 4). + + Valid values are: + + off or 0 + One interface of the bond is selected to be active, in order to + facilitate communication with peer devices that do not implement + LACP. + + on or 1 + Interfaces are only permitted to be made active if they have an + active LACP partner and have successfully reached + Collecting_Distributing state. + + The default value is 0 (off). + mode Specifies one of the bonding policies. The default is diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index be50125f0635..e044fc733b8c 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -6457,6 +6457,7 @@ static int __init bond_check_params(struct bond_params *params) params->ad_user_port_key = ad_user_port_key; params->coupled_control = 1; params->broadcast_neighbor = 0; + params->lacp_strict = 0; if (packets_per_slave > 0) { params->reciprocal_packets_per_slave = reciprocal_value(packets_per_slave); diff --git a/drivers/net/bonding/bond_netlink.c b/drivers/net/bonding/bond_netlink.c index 90365d3f7ebf..4a11572f663d 100644 --- a/drivers/net/bonding/bond_netlink.c +++ b/drivers/net/bonding/bond_netlink.c @@ -143,6 +143,7 @@ static const struct nla_policy bond_policy[IFLA_BOND_MAX + 1] = { [IFLA_BOND_NS_IP6_TARGET] = { .type = NLA_NESTED }, [IFLA_BOND_COUPLED_CONTROL] = { .type = NLA_U8 }, [IFLA_BOND_BROADCAST_NEIGH] = { .type = NLA_U8 }, + [IFLA_BOND_LACP_STRICT] = { .type = NLA_U8 }, }; static const struct nla_policy bond_slave_policy[IFLA_BOND_SLAVE_MAX + 1] = { @@ -599,6 +600,16 @@ static int bond_changelink(struct net_device *bond_dev, struct nlattr *tb[], return err; } + if (data[IFLA_BOND_LACP_STRICT]) { + int fallback_mode = nla_get_u8(data[IFLA_BOND_LACP_STRICT]); + + bond_opt_initval(&newval, fallback_mode); + err = __bond_opt_set(bond, BOND_OPT_LACP_STRICT, &newval, + data[IFLA_BOND_LACP_STRICT], extack); + if (err) + return err; + } + return 0; } @@ -671,6 +682,7 @@ static size_t bond_get_size(const struct net_device *bond_dev) nla_total_size(sizeof(struct in6_addr)) * BOND_MAX_NS_TARGETS + nla_total_size(sizeof(u8)) + /* IFLA_BOND_COUPLED_CONTROL */ nla_total_size(sizeof(u8)) + /* IFLA_BOND_BROADCAST_NEIGH */ + nla_total_size(sizeof(u8)) + /* IFLA_BOND_LACP_STRICT */ 0; } @@ -838,6 +850,10 @@ static int bond_fill_info(struct sk_buff *skb, bond->params.broadcast_neighbor)) goto nla_put_failure; + if (nla_put_u8(skb, IFLA_BOND_LACP_STRICT, + bond->params.lacp_strict)) + goto nla_put_failure; + if (BOND_MODE(bond) == BOND_MODE_8023AD) { struct ad_info info; diff --git a/drivers/net/bonding/bond_options.c b/drivers/net/bonding/bond_options.c index 5095ac3dad2c..f01b3baa57b4 100644 --- a/drivers/net/bonding/bond_options.c +++ b/drivers/net/bonding/bond_options.c @@ -68,6 +68,8 @@ static int bond_option_lacp_active_set(struct bonding *bond, const struct bond_opt_value *newval); static int bond_option_lacp_rate_set(struct bonding *bond, const struct bond_opt_value *newval); +static int bond_option_lacp_strict_set(struct bonding *bond, + const struct bond_opt_value *newval); static int bond_option_ad_select_set(struct bonding *bond, const struct bond_opt_value *newval); static int bond_option_queue_id_set(struct bonding *bond, @@ -162,6 +164,12 @@ static const struct bond_opt_value bond_lacp_rate_tbl[] = { { NULL, -1, 0}, }; +static const struct bond_opt_value bond_lacp_strict_tbl[] = { + { "off", 0, BOND_VALFLAG_DEFAULT}, + { "on", 1, 0}, + { NULL, -1, 0 } +}; + static const struct bond_opt_value bond_ad_select_tbl[] = { { "stable", BOND_AD_STABLE, BOND_VALFLAG_DEFAULT}, { "bandwidth", BOND_AD_BANDWIDTH, 0}, @@ -363,6 +371,14 @@ static const struct bond_option bond_opts[BOND_OPT_LAST] = { .values = bond_lacp_rate_tbl, .set = bond_option_lacp_rate_set }, + [BOND_OPT_LACP_STRICT] = { + .id = BOND_OPT_LACP_STRICT, + .name = "lacp_strict", + .desc = "Define the LACP fallback mode when no slaves have negotiated", + .unsuppmodes = BOND_MODE_ALL_EX(BIT(BOND_MODE_8023AD)), + .values = bond_lacp_strict_tbl, + .set = bond_option_lacp_strict_set + }, [BOND_OPT_MINLINKS] = { .id = BOND_OPT_MINLINKS, .name = "min_links", @@ -1685,6 +1701,16 @@ static int bond_option_lacp_rate_set(struct bonding *bond, return 0; } +static int bond_option_lacp_strict_set(struct bonding *bond, + const struct bond_opt_value *newval) +{ + netdev_dbg(bond->dev, "Setting LACP fallback to %s (%llu)\n", + newval->string, newval->value); + bond->params.lacp_strict = newval->value; + + return 0; +} + static int bond_option_ad_select_set(struct bonding *bond, const struct bond_opt_value *newval) { diff --git a/include/net/bond_options.h b/include/net/bond_options.h index e6eedf23aea1..52b966e92793 100644 --- a/include/net/bond_options.h +++ b/include/net/bond_options.h @@ -79,6 +79,7 @@ enum { BOND_OPT_COUPLED_CONTROL, BOND_OPT_BROADCAST_NEIGH, BOND_OPT_ACTOR_PORT_PRIO, + BOND_OPT_LACP_STRICT, BOND_OPT_LAST }; diff --git a/include/net/bonding.h b/include/net/bonding.h index edd1942dcd73..2c54a36a8477 100644 --- a/include/net/bonding.h +++ b/include/net/bonding.h @@ -129,6 +129,7 @@ struct bond_params { int peer_notif_delay; int lacp_active; int lacp_fast; + int lacp_strict; unsigned int min_links; int ad_select; char primary[IFNAMSIZ]; diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h index 363526549a01..43cecca49f01 100644 --- a/include/uapi/linux/if_link.h +++ b/include/uapi/linux/if_link.h @@ -1603,6 +1603,7 @@ enum { IFLA_BOND_NS_IP6_TARGET, IFLA_BOND_COUPLED_CONTROL, IFLA_BOND_BROADCAST_NEIGH, + IFLA_BOND_LACP_STRICT, __IFLA_BOND_MAX, }; diff --git a/tools/include/uapi/linux/if_link.h b/tools/include/uapi/linux/if_link.h index 97a2d4411534..757ce5e9426e 100644 --- a/tools/include/uapi/linux/if_link.h +++ b/tools/include/uapi/linux/if_link.h @@ -1527,6 +1527,7 @@ enum { IFLA_BOND_NS_IP6_TARGET, IFLA_BOND_COUPLED_CONTROL, IFLA_BOND_BROADCAST_NEIGH, + IFLA_BOND_LACP_STRICT, __IFLA_BOND_MAX, };