RE: question on random MAC in usbnet

[David Laight <David.Laight@ACULAB.COM>]

From: Bjørn Mork
> Sent: 16 November 2023 11:32
...
> > Do you think that behavior should be changed to using
> > a separate random MAC for each device that requires it?
> 
> I'm in favour.
> 
> I could be wrong, but I don't expect anything to break if we did that.
> The current static address comes from eth_random_addr() in any case, so
> the end result as seen from the mini drivers should be identical.  The
> difference will be seen in userspace and surrounding equipment, And
> those should be for the better.

It might cause grief when a USB device 'bounces' [1].
At the moment it will pick up the same 'random' MAC address.
But afterwards it will change.

So you might want to save the MAC on device removal and
re-use it on the next insert.

[1] We ended up putting the USB interface inside a 'bond'
in order to stop the interface everything was using
randomly disappearing due to common-mode noise on the
USB data lines causing a disconnect.

	David

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