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Subject: Re: [PATCH] Driver Core: devtmpfs - kernel-maintained tmpfs-based
 /dev
From: David Dillow <dave@thedillows.org>
To: Andi Kleen <andi@firstfloor.org>
Cc: Greg KH <greg@kroah.com>, Greg KH <gregkh@suse.de>,
       Alan Cox <alan@lxorguk.ukuu.org.uk>, linux-kernel@vger.kernel.org,
       Kay Sievers <kay.sievers@vrfy.org>, Jan Blunck <jblunck@suse.de>,
       Harald Hoyer <harald@redhat.com>,
       Scott James Remnant <scott@ubuntu.com>,
       Arjan van de Ven <arjan@infradead.org>
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Date: Tue, 11 Aug 2009 20:25:27 -0400
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On Tue, 2009-08-11 at 16:55 +0200, Andi Kleen wrote:
> > No, not really. It isn't hard to make a static /dev, or a rescue initrd
> > for the cases with dynamic device numbers.
> 
> There's a world between strictly controlled embedded and fully general
> distributions.

Sure, and I've acknowledged that. But it doesn't mean this needs a
kernel solution.

> I want a dynamic /dev, but a fast one that doesn't need initrd or
> slows down booting.

So use Eric/Arjan's program that does it in 60ms -- you get a
dynamic /dev, no initrd, fast boot, and no kernel changes required.

It remains to be seen how much it costs to do it in user space vs kernel
space. Arjan -- do you have a pointer to your program? Perhaps I can
shake loose some time to test that.