From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: [PATCH v3] net-tcp: TCP/IP stack bypass for loopback
 connections
Date: Wed, 19 Sep 2012 23:03:54 +0200
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To: David Miller <davem@davemloft.net>
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On Wed, 2012-09-19 at 16:34 -0400, David Miller wrote:

> I have an idea on how to handle this.
> 
> In drivers/net/loopback.c:loopback_tx(), skip the SKB orphan operation
> if there is a friend socket at skb->friend.
> 
> When sending such friend SKBs out at connection startup, arrange it
> such that the skb->destructor will zap the skb->friend pointer to
> NULL.
> 
> Also, in skb_orphan*(), if necessary, set skb->friend to NULL.
> 
> skb->sk will hold a reference to the socket, and since skb->friend
> will be equal, this will make sure a pointer to an unreferenced
> socket does not escape.

I now am wondering if we still need skb->friend field.

If skb->sk is not zeroed by a premature skb_orphan(), then

skb->sk->sk_friend gives the friend ?