Re: [PATCH net-next v6 5/9] net: dsa: microchip: ksz9477: Add Wake on Magic Packet support

From: Vladimir Oltean
Date: Fri Oct 20 2023 - 04:24:04 EST


On Fri, Oct 20, 2023 at 07:08:56AM +0200, Oleksij Rempel wrote:
> On Thu, Oct 19, 2023 at 08:29:53PM +0300, Vladimir Oltean wrote:
> > I don't get it, why do you release the reference on the MAC address as
> > soon as you successfully get it? Without a reference held, the
> > programmed address still lingers on, but the HSR offload code, on a
> > different port with a different MAC address, can change it and break WoL.
>
> It is ksz9477_get_wol() function. We do not actually need to program
> here the MAC address, we only need to test if we would be able to get
> it. To show the use more or less correct information on WoL
> capabilities. For example, instead showing the user that Wake on Magic
> is supported, where we already know that is not the case, we can already
> show correct information. May be it will be better to have
> extra option for ksz_switch_macaddr_get() to not allocate and do the
> refcounting or have a separate function.

Ah, yes, it is from get_wol(). Maybe a ksz_switch_macaddr_tryget(ds, port)
which returns bool (true if dev->switch_macaddr is NULL, or if non-NULL
and ether_addr_equal(dev->switch_macaddr->addr, port addr))?