From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [PATCH 0/3] net: time stamping fixes
Date: Wed, 19 Oct 2011 16:24:08 +0200
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Cc: Richard Cochran <richardcochran@gmail.com>,
	David Miller <davem@davemloft.net>, netdev@vger.kernel.org
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Wed, 2011-10-19 at 16:08 +0200, Eric Dumazet wrote:

> > Anyway, I guess you agree that the patches as-is aren't actually the
> > right solution since we can't sock_hold() a TX skb socket reference?
> 
> Yes, the sock_hold() could be changed by an atomic_inc_not_zero()
> 
> What about doing this ?

>  		if (likely(phydev->drv->txtstamp)) {
> +			if (!atomic_inc_not_zero(&sk->sk_refcnt))
> +				return;

Yeah that seems like it works and just drops the timestamp in case we
don't still have a live socket, which is perfectly fine.

johannes