From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: LRO/GRO and libpcap packet reordering
Date: Fri, 15 Mar 2013 00:16:20 +0100
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To: Andy Lutomirski <luto@amacapital.net>
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On Thu, 2013-03-14 at 15:58 -0700, Andy Lutomirski wrote:

> Right.  This is the part that I'm wondering about an efficient fix to
> (i.e. flush GRO state for one flow whenever a packet for the reversed
> flow is seen).

It doesnt seem doable easily, because network header and tcp headers are
handled in two separate functions in GRO stack (inet_gro_receive() &
tcp_gro_receive()

What you could do is changing MAX_GRO_SKBS from 8 to 1
(basically allowing only one flow in GRO stack)