Date: Tue, 12 Aug 2008 07:02:22 -0700
From: Arjan van de Ven <arjan@infradead.org>
To: Alan Cox <alan@lxorguk.ukuu.org.uk>
Cc: linux-kernel@vger.kernel.org, linux-ide@vger.kernel.org
Subject: Re: [patch 1/2] fastboot: Add a module parameter to skip probing of
 specific ports
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On Tue, 12 Aug 2008 13:00:27 +0100
Alan Cox <alan@lxorguk.ukuu.org.uk> wrote:

> > > What
> > > defines the probe order here particularly as people are pushing
> > > for parallel probing of multiple devices.
> > 
> > the patches I'm pushing for this don't change probe order; that has
> > been tried before and wasn't a great success.
> 
> That was a question sorry. You are sledgehammering controllers by
> discovery sequence - you've no idea if they will always be found in
> that order. As such your boot option is incredibly fragile.

ok to answer your question;
today the probe order is consistent, at least on netbooks.
The admin or his installation program knows it when he has this (and if
linux were to grow full parallel probing it'll be optional, and if the
admin wants a fast boot he'll disable the parallel, reordering probe)
and can add the option for this case. It's the "push policy out of the
kernel" thing.. while the kernel probably can't know this (and you're
right, the DMI patch is thus the wrong thing to do).. the admin can.


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