Commit a4ffe09f authored by Vladimir Oltean's avatar Vladimir Oltean Committed by David S. Miller
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net: dsa: still fast-age ports joining a bridge if they can't configure learning 



Commit 39f32101 ("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: default avatarVladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cfe908c1

net/dsa/port.c

+17 −1
Original line number Diff line number Diff line
@@ -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.