From mboxrd@z Thu Jan  1 00:00:00 1970
From: Rusty Russell <rusty@rustcorp.com.au>
Subject: Re: virtio_net: MAC address releated breakage if there is no MAC area in config
Date: Sun, 5 Apr 2009 14:11:07 +1030
Message-ID: <200904051311.08114.rusty@rustcorp.com.au>
References: <200904021333.25119.borntraeger@de.ibm.com>
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Cc: Alex Williamson <alex.williamson@hp.com>, netdev@vger.kernel.org,
	kvm@vger.kernel.org
To: Christian Borntraeger <borntraeger@de.ibm.com>
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On Thursday 02 April 2009 22:03:24 Christian Borntraeger wrote:
> I read this as the mac config field is optional (similar to all the optional
> fields we added in virtio_blk later).
> 
> I see two options:
> 1. Change our sample userspace to always allocate the config (like lguest and
> qemu)
> 2. Change the kernel code to not write into the config unless a specific feature
> bit is set. (e.g. VIRTIO_NET_F_SETMAC)

I had assumed it would always exist.  Agreed it's unclear; I'm currently
writing down the actual standard to avoid such mistakes in the future.

Cheers,
Rusty.