Re: [2.6 patch] drivers/net/loopback.c: convert to module_init()

[Stephen Hemminger <shemminger@osdl.org>]

On Tue, 12 Dec 2006 17:17:56 -0800 (PST)
David Miller <davem@davemloft.net> wrote:

> From: Adrian Bunk <bunk@stusta.de>
> Date: Tue, 12 Dec 2006 17:24:35 +0100
> 
> > This patch converts drivers/net/loopback.c to using module_init().
> > 
> > Signed-off-by: Adrian Bunk <bunk@stusta.de>
> 
> I'm not %100 sure of this one, let's look at the comment you
> are deleting:
> 
> > -/*
> > - *	The loopback device is global so it can be directly referenced
> > - *	by the network code. Also, it must be first on device list.
> > - */
> > -extern int loopback_init(void);
> > -
> 
> in particular notice the part that says "it must be first on the
> device list".
> 
> I'm not sure whether that is important any longer.  It probably isn't,
> but we should verify it before applying such a patch.
> 
> Since module_init() effectively == device_initcall() for statically
> built objects, which loopback always is, the Makefile ordering does
> not seem to indicate to me that there is anything guarenteeing
> this "first on the list" invariant.  At least not via object
> file ordering.
> 
> So this gives some support to the idea that loopback_dev's position
> on the device list no longer matters.

The dst code makes assumptions that loopback is ifindex 1 as well.
NAK on Adrian's change, it doesn't buy anything