From mboxrd@z Thu Jan  1 00:00:00 1970
From: Johannes Berg <johannes@sipsolutions.net>
Subject: Re: [PATCH] net-tcp: fix panic in tcp_fastopen_cache_set()
Date: Thu, 14 Nov 2013 21:53:23 +0100
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Cc: Dave Jones <davej@redhat.com>, David Miller <davem@davemloft.net>,
	netdev@vger.kernel.org, Yuchung Cheng <ycheng@google.com>
To: Eric Dumazet <eric.dumazet@gmail.com>
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On Thu, 2013-11-14 at 11:38 -0800, Eric Dumazet wrote:

> > > Doesn't that __sk_dst_get() have to go inside the rcu_read_lock()?
> > > 
> > > Then again, I guess we hold the socket. Still looks a bit weird to be
> > > moving it out.
> > 
> > Yep, in fact this rcu_read_lock() is not needed. I'll send a v2.
> 
> I take it back.
> 
> the rcu_read_lock() protects the tcp_get_metrics(), not the
> __sk_dst_get(sk)
> 
> So the patch is correct, unless you disagree of course ;)

Heh. I have no idea, it just seemed a little odd on first look given
that __sk_dst_get() *can* actually use RCU protection. :)

johannes