From mboxrd@z Thu Jan  1 00:00:00 1970
From: Eric Dumazet <eric.dumazet@gmail.com>
Subject: Re: route.c:645 suspicious rcu_dereference_check()
Date: Fri, 31 Aug 2012 04:50:14 -0700
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To: David Miller <davem@davemloft.net>
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On Thu, 2012-08-30 at 13:34 -0400, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Tue, 28 Aug 2012 15:33:07 -0700
> 
> > From: Eric Dumazet <edumazet@google.com>
> > 
> > [PATCH] ipv4: must use rcu protection while calling fib_lookup
> > 
> > Following lockdep splat was reported by Pavel Roskin :
>  ...
> > Signed-off-by: Eric Dumazet <edumazet@google.com>
> > Reported-by: Pavel Roskin <proski@gnu.org>
> 
> Applied, thanks.
> 
> It looks like the redirect handlers might have the same problem?

Hi David

Correct me if I am wrong, but redirect handlers should all run under
rcu_read_lock() protection already.

rcu_read_lock() is done in ip_local_deliver_finish() or
ip_rt_send_redirect() for the forward path.

And above of them, we also have rcu_read_lock() done in
__netif_receive_skb()