[PATCH net-next v4 10/14] net: bridge: mcast: track active state, bridge up/down
From: Linus Lüssing <hidden>
Date: 2026-03-07 04:46:17
Also in:
bridge, linux-kselftest, lkml
Subsystem:
ethernet bridge, networking drivers, networking [general], the rest · Maintainers:
Nikolay Aleksandrov, Ido Schimmel, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
This is mainly for switchdev and DSA later: To ensure that we switch to inactive before destroying a bridge interface. A switchdev/DSA driver might have allocated resources after we switched to an enabled multicast active state. This gives switchdev/DSA drivers a chance to free these resources again when we destroy the bridge (later). Putting it into the ndo_stop / bridge interface down part instead of the ndo_uninit / bridge destroy part though for a better semantic match. If the bridge interface is down / stopped then it is also inactive. No functional change for the fast/data path. Signed-off-by: Linus Lüssing <redacted> --- include/uapi/linux/if_link.h | 8 ++++---- net/bridge/br_multicast.c | 12 ++++++++++++ 2 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/include/uapi/linux/if_link.h b/include/uapi/linux/if_link.h
index d963be8679b5..679368784643 100644
--- a/include/uapi/linux/if_link.h
+++ b/include/uapi/linux/if_link.h@@ -748,14 +748,14 @@ enum in6_addr_gen_mode { * @IFLA_BR_MCAST_ACTIVE_V4 * Bridge IPv4 mcast active state, read only. * - * 1 if *IFLA_BR_MCAST_SNOOPING* is enabled and an IGMP querier is present, - * 0 otherwise. + * 1 if *IFLA_BR_MCAST_SNOOPING* is enabled, an IGMP querier is present + * and the bridge interface is up, 0 otherwise. * * @IFLA_BR_MCAST_ACTIVE_V6 * Bridge IPv6 mcast active state, read only. * - * 1 if *IFLA_BR_MCAST_SNOOPING* is enabled and an MLD querier is present, - * 0 otherwise. + * 1 if *IFLA_BR_MCAST_SNOOPING* is enabled, an MLD querier is present + * and the bridge interface is up, 0 otherwise. */ enum { IFLA_BR_UNSPEC,
diff --git a/net/bridge/br_multicast.c b/net/bridge/br_multicast.c
index 1059984d8147..cb78f9555db6 100644
--- a/net/bridge/br_multicast.c
+++ b/net/bridge/br_multicast.c@@ -1124,6 +1124,7 @@ static void br_multicast_notify_active(struct net_bridge_mcast *brmctx, * * The multicast active state is set, per protocol family, if: * + * - the bridge interface is up * - multicast snooping is enabled * - an IGMP/MLD querier is present * - for own IPv6 MLD querier: an IPv6 link-local address is configured on the
@@ -1142,6 +1143,11 @@ static void br_multicast_update_active(struct net_bridge_mcast *brmctx) lockdep_assert_held_once(&brmctx->br->multicast_lock); + if (!netif_running(brmctx->br->dev)) { + force_inactive = true; + goto update; + } + if (!br_opt_get(brmctx->br, BROPT_MULTICAST_ENABLED)) { force_inactive = true; goto update;
@@ -4431,6 +4437,9 @@ static void __br_multicast_open(struct net_bridge_mcast *brmctx) #if IS_ENABLED(CONFIG_IPV6) __br_multicast_open_query(brmctx->br, &brmctx->ip6_own_query); #endif + + /* bridge interface is up, maybe set multicast state to active */ + br_multicast_update_active(brmctx); } static void br_multicast_open_locked(struct net_bridge *br)
@@ -4478,6 +4487,9 @@ static void __br_multicast_stop(struct net_bridge_mcast *brmctx) timer_shutdown(&brmctx->ip6_other_query.delay_timer); timer_shutdown(&brmctx->ip6_own_query.timer); #endif + + /* bridge interface is down, set multicast state to inactive */ + br_multicast_update_active(brmctx); } void br_multicast_update_vlan_mcast_ctx(struct net_bridge_vlan *v, u8 state)
--
2.53.0