Re: [PATCH net-next 2/2] net: dsa: lan9303: Add basic offloading of unicast traffic

From: Egil Hjelmeland
Date: Sun Sep 24 2017 - 18:02:20 EST


Den 23. sep. 2017 16:31, skrev Andrew Lunn:
The point is: Once both external ports are in "forwarding", I see no way
to prevent traffic flowing directly between the external ports.

Generally, there are port vectors. Port X can send frames only to Port
Y.

If you don't have that, there are possibilities with VLANs. Each port
is given a unique VLAN. All incoming untagged traffic is tagged with
the VLAN. You just need to keep the VLAN separated and add/remove the
VLAN tag in the dsa tag driver.

Andrew

Thanks. The lan9303 has nothing like "port vectors". The port tagging
scheme is VLAN based, but is does not prevent direct forwarding between
the external ports.

In order to not break the strong port separation in the current driver;
I will stick to my solution, and only add caching of the STP state
register.

Egil