RE: [PATCH net-next v3 0/5] net: dsa: remove .set_addr

[Rodney Cummings]

PAUSE is only one higher layer entity. The source MAC address may not matter there, but it definitely matters for other higher layer entities (like IEEE Std 1588).

The Marvell switch can run more than just PAUSE as a higher layer protocol.

How do you guarantee that this MAC address is used for PAUSE, and only for PAUSE?

> -----Original Message-----
> From: Andrew Lunn [mailto:andrew@xxxxxxx]
> Sent: Monday, October 16, 2017 11:48 AM
> To: Rodney Cummings <rodney.cummings@xxxxxx>
> Cc: Vivien Didelot <vivien.didelot@xxxxxxxxxxxxxxxxxxxx>;
> netdev@xxxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx;
> kernel@xxxxxxxxxxxxxxxxxxxx; David S. Miller <davem@xxxxxxxxxxxxx>;
> Florian Fainelli <f.fainelli@xxxxxxxxx>; David Laight
> <David.Laight@xxxxxxxxxx>
> Subject: Re: [PATCH net-next v3 0/5] net: dsa: remove .set_addr
> 
> On Mon, Oct 16, 2017 at 04:28:04PM +0000, Rodney Cummings wrote:
> > Hi Andrew,
> >
> > I may have misunderstood.
> >
> > If this MAC address is the destination
> 
> Nope. This is the source address, for Pause frames.
> 
> > My concern is that for a source MAC address, a local random MAC
> > address is not safe in all networks, because it has the potential
> > for duplication. That topic has been discussed quite a bit in IEEE
> > 802.
> 
> Duplications don't matter, for pause frames. The source address
> appears to be unused. And these frames don't get passed the direct
> peers MAC layer.
> 
> 	Andrew