From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <cwang@twopensource.com>
Subject: Re: [PATCH net] ipv6: introduce tcp_v6_iif()
Date: Fri, 17 Oct 2014 09:58:24 -0700
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Cc: David Miller <davem@davemloft.net>, netdev <netdev@vger.kernel.org>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Fri, Oct 17, 2014 at 9:17 AM, Eric Dumazet <eric.dumazet@gmail.com> wrote:
> From: Eric Dumazet <edumazet@google.com>
>
> Commit 971f10eca186 ("tcp: better TCP_SKB_CB layout to reduce cache line
> misses") added a regression for SO_BINDTODEVICE on IPv6.
>
> This is because we still use inet6_iif() which expects that IP6 control
> block is still at the beginning of skb->cb[]
>
> This patch adds tcp_v6_iif() helper and uses it where necessary.
>
> Because __inet6_lookup_skb() is used by TCP and DCCP, we add an iif
> parameter to it.
>

I doubt we still need to store iif in IP6CB() since we have skb->skb_iif,
we can probably just make inet6_iif() be like inet_iif() so that IP6CB()->iif
can be just removed? Does this make any sense to you?

(I have a patch locally since I thought it should be target for net-next.)

Thanks.