[PATCH] kernel: DSA roaming fix for Marvell Link Street switch series

[DENG Qingfang]

On Tue, Feb 2, 2021 at 8:14 PM Tad <tad at spotco.us> wrote:
>
> I've tested this working well!
> Devices can roam during iperf with no loss!
> Thank you!
>
>
> There are some errors in dmesg:
> wrt1900acv1
> mv88e6085 f1072004.mdio-mii:00: ATU member violation for [mac] portvec 20 spid 3
>
> wrt1200ac
> mv88e6085 f1072004.mdio-mii:00: ATU member violation for [mac] portvec 40 spid 3
>
> are those expected?

I think so. When your client moves back to the switch ports, the
static entry in the ATU still points to the CPU port, so it triggers
an ATU member violation interrupt. DSA will clear the static entry
afterward so it is not fatal.

Tobias, what happens if the switch receives a frame that violates ATU
portvec member? Is the frame trapped to the CPU or dropped? Is it okay
to suppress this warning?