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Date: Mon, 20 Sep 2010 10:34:57 +0100
From: Stefan Hajnoczi <stefanha@linux.vnet.ibm.com>
Subject: Re: [Qemu-devel] [PATCH] e1000: Pad short frames to minimum size
	(60 bytes)
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To: "Edgar E. Iglesias" <edgar.iglesias@gmail.com>
Cc: Kevin Wolf <kwolf@redhat.com>, Stefan Hajnoczi <stefanha@gmail.com>, 638955@bugs.launchpad.net, qemu-devel@nongnu.org, "Michael S. Tsirkin" <mst@redhat.com>

On Mon, Sep 20, 2010 at 11:03:37AM +0200, Edgar E. Iglesias wrote:
> On Mon, Sep 20, 2010 at 10:50:40AM +0200, Kevin Wolf wrote:
> > Am 19.09.2010 08:36, schrieb Stefan Hajnoczi:
> > > On Sat, Sep 18, 2010 at 10:27 PM, Edgar E. Iglesias
> > > <edgar.iglesias@gmail.com> wrote:
> > >> This doesn't look right. AFAIK, MAC's dont pad on receive.
> > > 
> > > I agree.  NICs that do padding will do it on transmit, not receive.
> > > Anything coming in on the wire should already have the minimum length.
> > > 
> > > In QEMU that isn't true today and that's why rtl8139, pcnet, and
> > > ne2000 already do this same padding.  This patch is the smallest
> > > change to cover e1000.
> > 
> > What's the reason that it isn't true in QEMU today? Shouldn't we fix
> > these problems rather than making device emulations incorrect to
> > compensate for it?
> 
> Yes we should, I agree.

Does someone with more knowledge for QEMU networking than me want to
take a stab at it?

Stefan