From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] tcp: gso: fix truesize tracking
Date: Tue, 29 Oct 2013 00:05:36 -0400 (EDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Fri, 25 Oct 2013 17:26:17 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> commit 6ff50cd55545 ("tcp: gso: do not generate out of order packets")
> had an heuristic that can trigger a warning in skb_try_coalesce(),
> because skb->truesize of the gso segments were exactly set to mss.
> 
> This breaks the requirement that
> 
> skb->truesize >= skb->len + truesizeof(struct sk_buff);
> 
> It can trivially be reproduced by :
> 
> ifconfig lo mtu 1500
> ethtool -K lo tso off
> netperf
> 
> As the skbs are looped into the TCP networking stack, skb_try_coalesce()
> warns us of these skb under-estimating their truesize.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>
> Reported-by: Alexei Starovoitov <ast@plumgrid.com>

I decided to apply this to 'net' and queue it up for -stable,
thanks Eric!