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Subject: Re: [PATCH] Driver Core: devtmpfs - kernel-maintained tmpfs-based
 /dev
From: David Dillow <dave@thedillows.org>
To: Greg KH <greg@kroah.com>
Cc: Andi Kleen <andi@firstfloor.org>, 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: Wed, 12 Aug 2009 08:56:53 -0400
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On Tue, 2009-08-11 at 17:34 -0700, Greg KH wrote:
> On Tue, Aug 11, 2009 at 08:25:27PM -0400, David Dillow wrote:
> > 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.
> 
> Their program only handles it for a reconstruction of /dev based on
> sysfs one time at boot.  It does not handle things that are added or
> discovered by the system after that, you need udev for that.
> 
> So it's a great hack for boot time stuff, but not a complete /dev
> management replacement like this code can be for numerous systems.

What systems would those be? Perhaps it's just too early in the morning
for me, but I'm having a hard time thinking of ones that wouldn't want
to use udev in that case for the event notification, or have their own
handler, such as an embedded system.