From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: something is wrong in commit 971f10eca1 - tcp: better
 TCP_SKB_CB layout to reduce cache line misses
Date: Wed, 15 Oct 2014 04:27:02 -0700
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Cc: Cong Wang <cwang@twopensource.com>,
	David Miller <davem@davemloft.net>,
	Eric Dumazet <edumazet@gmail.com>,
	netdev <netdev@vger.kernel.org>
To: Krzysztof Kolasa <kkolasa@winsoft.pl>
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On Wed, 2014-10-15 at 12:35 +0200, Krzysztof Kolasa wrote:
> W dniu 14.10.2014 o 23:43, Eric Dumazet pisze:
> > On Tue, 2014-10-14 at 14:24 -0700, Cong Wang wrote:
> >
> >> Since we are still in merge window, I don't think we have to use
> >> a one-line fix for a bug introduced in this merge window.
> > You are clearly refactoring here. Its a nice cleanup.
> >
> > If I was the maintainer, I would prefer the one line fix.
> >
> > Then when net-next is open, you refactor.
> >
> > As I said, I wont argue, do whatever you want.
> >
> > Thanks
> >
> >
> >
> 
> one-line patch not resolve problem, fix created by Cong Wang resolves 
> problem !!!

Hmm, there should be no difference with either patch.

tcp_v4_rcv() 
...
memmove(&TCP_SKB_CB(skb)->header.h4, IPCB(skb),
        sizeof(struct inet_skb_parm));
...
-> tcp_v4_do_rcv() 
   ->  tcp_v4_hnd_req()
      -> cookie_v4_check(... , &TCP_SKB_CB(skb)->header.h4.opt)

Hmm...