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Date: Fri, 7 Jun 2013 14:29:12 +0200
From: Stefan Hajnoczi <stefanha@gmail.com>
Message-ID: <20130607122912.GB11350@stefanha-thinkpad.redhat.com>
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Subject: Re: [Qemu-devel] difference between receive_raw() and receive()
 NetClientInfo methods ?
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To: Luigi Rizzo <rizzo@iet.unipi.it>
Cc: Giuseppe Lettieri <g.lettieri@iet.unipi.it>, qemu-devel <qemu-devel@nongnu.org>, Vincenzo Maffione <v.maffione@gmail.com>

On Thu, Jun 06, 2013 at 11:40:37AM +0200, Luigi Rizzo wrote:
> Can someone clarify what is the difference between the two methods
> r
> eceive_raw() and receive() in NetClientInfo ?

receive_raw() builds an empty vnet header, if necessary.  It is used to
send a gratuitous ARP reply from inside QEMU.

In the case where the NIC and its peer use vnet headers, packets
generated by QEMU internally cannot use ->receive() since they don't
know how to use the vnet header.  ->receive_raw() takes care of that.

Stefan