From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 1/2] tcp: provide skb->hash to synack packets
Date: Thu, 17 Sep 2015 21:01:13 -0700 (PDT)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Tue, 15 Sep 2015 15:24:20 -0700

> From: Eric Dumazet <edumazet@google.com>
> 
> In commit b73c3d0e4f0e ("net: Save TX flow hash in sock and set in skbuf
> on xmit"), Tom provided a l4 hash to most outgoing TCP packets.
> 
> We'd like to provide one as well for SYNACK packets, so that all packets
> of a given flow share same txhash, to later enable bonding driver to
> also use skb->hash to perform slave selection.
> 
> Note that a SYNACK retransmit shuffles the tx hash, as Tom did
> in commit 265f94ff54d62 ("net: Recompute sk_txhash on negative routing
> advice") for established sockets.
> 
> This has nice effect making TCP flows resilient to some kind of black
> holes, even at connection establish phase.
> 
> Signed-off-by: Eric Dumazet <edumazet@google.com>

Applied.