From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next 5/7] qlcnic: fix default operating state of
 interface
Date: Fri, 17 Jun 2011 00:10:35 -0400 (EDT)
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Cc: netdev@vger.kernel.org, amit.salecha@qlogic.com
To: anirban.chakraborty@qlogic.com
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From: Anirban Chakraborty <anirban.chakraborty@qlogic.com>
Date: Thu, 16 Jun 2011 13:37:36 -0700

> From: Amit Kumar Salecha <amit.salecha@qlogic.com>
> 
> Currently interface shows status as RUNNING, even if there is no link.
> To fix this, netif_carrier_off should be called after register_netdev().
> 
> netif_carrier_off calls linkwatch_fire_event(dev); only if netdev is registered,
> otherwise it skips. linkwatch_fire_event set default state of nic interface.
> 
> Signed-off-by: Amit Kumar Salecha <amit.salecha@qlogic.com>
> Signed-off-by: Anirban Chakraborty <anirban.chakraborty@qlogic.com>

You cannot do this.

The exact second that register_netdev() is called, the device can
be brought up asynchronously and the link brought into the up state.

Your netif_carrier_off() call will race with this.

This is why no other (properly functioning) driver does what you're
trying to do here.