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To: viro@parcelfarce.linux.theplanet.co.uk
Cc: Linus Torvalds <torvalds@osdl.org>, Daniel Jacobowitz <dan@debian.org>,
       Andries Brouwer <aebr@win.tue.nl>, Rob Love <rml@ximian.com>,
       rob@landley.net, Pascal Schmidt <der.eremit@email.de>,
       linux-kernel@vger.kernel.org, Greg KH <greg@kroah.com>
Subject: Re: udev and devfs - The final word
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From: ebiederm@xmission.com (Eric W. Biederman)
Date: 04 Jan 2004 22:26:37 -0700
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viro@parcelfarce.linux.theplanet.co.uk writes:

> On Sun, Jan 04, 2004 at 08:02:20PM -0800, Linus Torvalds wrote:
> > Now, we'd probably not want to force the switch, but I do suspect we'll 
> > have exactly this as a switch in the "Kernel Debugging Config" section. 
> > Where even _common_ things like disks could end up with per-bootup values. 
> > Just to verify that every part of the system ends up having it right.
> 
> Then we'd better have a very good idea of the things that are going to
> break.  Note that right now even late-boot code in kernel itself will
> break on that - there are explicit checks for ROOT_DEV==MKDEV(2,0),
> all sorts of weird crap deep in the bowels of arch/ppc/*/*, etc.

/sbin/lilo and possibly some of the other bootloaders.  Relationships
between devices are a challenge to work with.  How do you go from a
partition to it's actual block device etc.  I don't remember how many
major numbers lilo has hard coded, I just remember looking at it once
and realizing I couldn't think of a better way to accomplish what it
was trying to do.

Eric