From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next-2.6] net: dummy: add auto_up module parameter
Date: Mon, 06 Dec 2010 12:36:46 -0800 (PST)
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From: Octavian Purdila <opurdila@ixiacom.com>
Date: Tue, 30 Nov 2010 17:57:27 +0200

> Add auto_up module parameter to automatically bring up the created
> devices. This is useful when using the dummy driver for testing net
> device register / unregister performance.
> 
> Signed-off-by: Octavian Purdila <opurdila@ixiacom.com>

Registering a new netdevice with IFF_UP set is an error.  You can't
set IFF_UP without also doing all of the other work, callbacks, and
state changes which are made by dev_open()'s code paths.

If, as you say, your interests are in testing register/unregister
performance, you can do that by making the appropriate calls in a loop
from userspace.

I honestly don't see what you hope to gain with this change, and
anyways since the registration state is basically illegal you'll need
to find another way to do this.