Date: Wed, 15 Sep 2004 09:12:29 -0700
From: Greg KH <greg@kroah.com>
To: "Giacomo A. Catenazzi" <cate@debian.org>
Cc: Tonnerre <tonnerre@thundrix.ch>, Ian Campbell <icampbell@arcom.com>,
       "Marco d'Itri" <md@Linux.IT>,
       Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: udev is too slow creating devices
Message-ID: <20040915161227.GC21971@kroah.com>
References: <414757FD.5050209@pixelized.ch> <20040914213506.GA22637@kroah.com> <20040914214552.GA13879@wonderland.linux.it> <20040914215122.GA22782@kroah.com> <20040914224731.GF3365@dualathlon.random> <20040914230409.GA23474@kroah.com> <414849CE.8080708@debian.org> <1095258966.18800.34.camel@icampbell-debian> <20040915152019.GD24818@thundrix.ch> <4148637F.9060706@debian.org>
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On Wed, Sep 15, 2004 at 05:45:03PM +0200, Giacomo A. Catenazzi wrote:
> 
> 
> Tonnerre wrote:
> >
> >On Wed, Sep 15, 2004 at 03:36:06PM +0100, Ian Campbell wrote:
> >
> >>I wonder if it would be feasible for modprobe (or some other utility) to
> >>have a new option: --wait-for=/dev/something which would wait for the
> >>device node to appear. Perhaps by:
> >>	- some mechanism based on HAL, DBUS, whatever
> >>	- dnotify on /dev/?
> >>	- falling back to spinning and waiting.
> >
> >
> >This would  end up  as hideous misfeature  as you can't  guarantee the
> >device to show up *at* *all*.
> >
> >The reason udev is there is that we can dynamically respond to created
> >device nodes and  devices that show up. They  might have changed since
> >the last boot. Maybe they don't show up at all.
> >
> >Thus you should trigger your actions from /etc/dev.d.
> 
> It is right.
> But an option --wait would be sufficient.
> This option will require modprobe to wait (with a timeout of
> x seconds) that hotplug event finish (so if device is created or
> not is no more a problem).
> Ideally this should be done modifing only hotplug and IMHO
> should be enabled by default.

Um, I don't think this is posible to do at all.  But hey, go ahead and
implement it to prove me wrong :)

good luck,

greg k-h
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