From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [Patch net-next v3] netpoll: fix a rtnl lock assertion failure
Date: Mon, 14 Jan 2013 18:13:50 -0500 (EST)
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From: Eric Dumazet <eric.dumazet@gmail.com>
Date: Mon, 14 Jan 2013 09:09:56 -0800

> On Mon, 2013-01-14 at 09:07 -0800, Eric Dumazet wrote:
> 
>> Strange, why dont we call netdev_master_upper_dev_get() instead ?
>> 
>> 
> 
> What I meant is : the result of this check might be of little use, if we
> don't hold any lock preventing another thread to change things behind
> us.

Agreed, this test is going to be racey.