Commit f2f3729f authored Sep 28, 2020 by Nikolay Aleksandrov Committed by David S. Miller Sep 28, 2020

net: bridge: fdb: don't flush ext_learn entries



When a user-space software manages fdb entries externally it should
set the ext_learn flag which marks the fdb entry as externally managed
and avoids expiring it (they're treated as static fdbs). Unfortunately
on events where fdb entries are flushed (STP down, netlink fdb flush
etc) these fdbs are also deleted automatically by the bridge. That in turn
causes trouble for the managing user-space software (e.g. in MLAG setups
we lose remote fdb entries on port flaps).
These entries are completely externally managed so we should avoid
automatically deleting them, the only exception are offloaded entries
(i.e. BR_FDB_ADDED_BY_EXT_LEARN + BR_FDB_OFFLOADED). They are flushed as
before.

Fixes: eb100e0e ("net: bridge: allow to add externally learned entries from user-space")
Signed-off-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

parent a4be47af

net/bridge/br_fdb.c

+2 −0

Original line number	Diff line number	Diff line
		@@ -413,6 +413,8 @@ void br_fdb_delete_by_port(struct net_bridge *br,

		if (!do_all)
		if (test_bit(BR_FDB_STATIC, &f->flags) \|\|
		(test_bit(BR_FDB_ADDED_BY_EXT_LEARN, &f->flags) &&
		!test_bit(BR_FDB_OFFLOADED, &f->flags)) \|\|
		(vid && f->key.vlan_id != vid))
		continue;

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