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Message-ID: <1369150693.3301.233.camel@edumazet-glaptop>
Subject: Re: [PATCH] rcu: fix a race in hlist_nulls_for_each_entry_rcu macro
From: Eric Dumazet <eric.dumazet@gmail.com>
To: Roman Gushchin <klamm@yandex-team.ru>
Cc: paulmck@linux.vnet.ibm.com, Dipankar Sarma <dipankar@in.ibm.com>,
        zhmurov@yandex-team.ru, linux-kernel@vger.kernel.org,
        netdev@vger.kernel.org, "David S. Miller" <davem@davemloft.net>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>,
        James Morris <jmorris@namei.org>,
        Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>,
        Patrick McHardy <kaber@trash.net>
Date: Tue, 21 May 2013 08:38:13 -0700
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On Tue, 2013-05-21 at 18:47 +0400, Roman Gushchin wrote:

> This code has the same mistake: it is rcu_dereference_raw(head->first), 
> so there is nothing that prevents gcc to store the (head->first) value 
> in a register.

If other rcu accessors have the same problem, a more complete patch is
needed.

Thanks