From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wei Liu <wei.liu2@citrix.com>
Subject: Re: [PATCH net-next v4 2/5] xen-netback: add support for IPv6
 checksum offload from guest
Date: Mon, 14 Oct 2013 11:42:35 +0100
Message-ID: <20131014104235.GB11739@zion.uk.xensource.com>
References: <1381503982-1418-1-git-send-email-paul.durrant@citrix.com>
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Cc: <xen-devel@lists.xen.org>, <netdev@vger.kernel.org>,
	Wei Liu <wei.liu2@citrix.com>,
	David Vrabel <david.vrabel@citrix.com>,
	Ian Campbell <ian.campbell@citrix.com>
To: Paul Durrant <paul.durrant@citrix.com>
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On Fri, Oct 11, 2013 at 04:06:19PM +0100, Paul Durrant wrote:
[...]
> -/*
> - * This is the amount of packet we copy rather than map, so that the
> - * guest can't fiddle with the contents of the headers while we do
> - * packet processing on them (netfilter, routing, etc).
> +/* This is a miniumum size for the linear area to avoid lots of
> + * calls to __pskb_pull_tail() as we set up checksum offsets.
>   */

You seem to forget to explain why 128 is chosen. :-)

Wei.