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Date: Wed, 23 Nov 2016 06:26:41 +0200
From: "Michael S. Tsirkin" <mst@redhat.com>
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Subject: Re: [Qemu-devel] [RFC v2 0/3] virtio-net: Add support to MTU feature
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To: Jason Wang <jasowang@redhat.com>
Cc: Maxime Coquelin <maxime.coquelin@redhat.com>, yuanhan.liu@linux.intel.com, pbonzini@redhat.com, Aaron Conole <aconole@redhat.com>, qemu-devel@nongnu.org

On Wed, Nov 23, 2016 at 11:42:52AM +0800, Jason Wang wrote:
> > > > > > > >  Seems to me like an easy way to get out of sync.
> > > > > >
> > > > > >If we send it to the backend, that has a chance to check
> > > > > >mtu and disconnect on error.
> > > >
> > > >For vhost-user backend, we can send it the MTU value with a
> > > >vhost-user protocol feature.
> > > >
> > > >For tun/macvtap, how do you do without adding a new ioctl ?
> > Have management configure same mtu on the backend and in qemu.
> > 
> > 
> 
> Then why not do same for vhost-user (instead of using two different
> methods)?

That's what I'm saying. If backend supports that, we can also
check the mtu in some way to make sure it matches.

-- 
MST