From mboxrd@z Thu Jan  1 00:00:00 1970
From: Cong Wang <amwang@redhat.com>
Subject: Re: [Patch net-next v4] netpoll: fix a rtnl lock assertion failure
Date: Thu, 17 Jan 2013 12:00:45 +0800
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Cc: eric.dumazet@gmail.com, netdev@vger.kernel.org, jiri@resnulli.us
To: David Miller <davem@davemloft.net>
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On Wed, 2013-01-16 at 22:52 -0500, David Miller wrote:
> From: Eric Dumazet <eric.dumazet@gmail.com>
> Date: Wed, 16 Jan 2013 17:24:45 -0800
> 
> >>  	if (np->dev_name)
> >> -		ndev = dev_get_by_name(&init_net, np->dev_name);
> >> +		ndev = __dev_get_by_name(&init_net, np->dev_name);
>  ...
> > Please revert this part.
> 
> You mean just revert that hunk above that made it use the
> non-refcounting version of dev_get_by_name()?

But there is no reason to take both rtnl lock and RCU read lock,
although that is fine.

I think just adding dev_hold() is enough.