From a4ffe09fc2d7138d28b225cc20893f506f2712cf Mon Sep 17 00:00:00 2001 From: Vladimir Oltean Date: Mon, 9 Aug 2021 01:56:48 +0300 Subject: [PATCH] net: dsa: still fast-age ports joining a bridge if they can't configure learning Commit 39f32101543b ("net: dsa: don't fast age standalone ports") assumed that all standalone ports disable address learning, but if the switch driver implements .port_fast_age but not .port_bridge_flags (like ksz9477, ksz8795, lantiq_gswip, lan9303), then that might not actually be true. So whereas before, the bridge temporarily walking us through the BLOCKING STP state meant that the standalone ports had a checkpoint to flush their baggage and start fresh when they join a bridge, after that commit they no longer do. Restore the old behavior for these drivers by checking if the switch can toggle address learning. If it can't, disregard the "do_fast_age" argument and unconditionally perform fast ageing on STP state changes. Signed-off-by: Vladimir Oltean Signed-off-by: David S. Miller --- net/dsa/port.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/net/dsa/port.c b/net/dsa/port.c index 96a4de67eccb..aac87ac989ed 100644 --- a/net/dsa/port.c +++ b/net/dsa/port.c @@ -60,6 +60,21 @@ static void dsa_port_fast_age(const struct dsa_port *dp) dsa_port_notify_bridge_fdb_flush(dp); } +static bool dsa_port_can_configure_learning(struct dsa_port *dp) +{ + struct switchdev_brport_flags flags = { + .mask = BR_LEARNING, + }; + struct dsa_switch *ds = dp->ds; + int err; + + if (!ds->ops->port_bridge_flags || !ds->ops->port_pre_bridge_flags) + return false; + + err = ds->ops->port_pre_bridge_flags(ds, dp->index, flags, NULL); + return !err; +} + int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age) { struct dsa_switch *ds = dp->ds; @@ -70,7 +85,8 @@ int dsa_port_set_state(struct dsa_port *dp, u8 state, bool do_fast_age) ds->ops->port_stp_state_set(ds, port, state); - if (do_fast_age && dp->learning) { + if (!dsa_port_can_configure_learning(dp) || + (do_fast_age && dp->learning)) { /* Fast age FDB entries or flush appropriate forwarding database * for the given port, if we are moving it from Learning or * Forwarding state, to Disabled or Blocking or Listening state. -- 2.11.0