Re: [PATCH 0/3] Fix for KSZ DSA switch shutdown

[Vladimir Oltean]

 On Fri, Sep 10, 2021 at 01:51:56PM +0200, Andrew Lunn wrote:
> > It does not really scale but we also don't have that many DSA masters to
> > support, I believe I can name them all: bcmgenet, stmmac, bcmsysport, enetc,
> > mv643xx_eth, cpsw, macb.
> 
> fec, mvneta, mvpp2, i210/igb.

I can probably double that list only with Freescale/NXP Ethernet
drivers, some of which are not even submitted to mainline. To name some
mainline drivers: gianfar, dpaa-eth, dpaa2-eth, dpaa2-switch, ucc_geth.
Also consider that DSA/switchdev drivers can also be DSA masters of
their own, we have boards doing that too.

Anyway, I've decided to at least try and accept the fact that DSA
masters will unregister their net_device on shutdown, and attempt to do
something sane for all DSA switches in that case.

Attached are two patches (they are fairly big so I won't paste them
inline, and I would like initial feedback before posting them to the
list).

As mentioned in those patches, the shutdown ordering guarantee is still
very important, I still have no clue what goes on there, what we need to
do, etc.