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Date: Fri, 13 Apr 2007 15:24:53 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: "Markus Rechberger" <markus.rechberger@amd.com>
Cc: "Alan Stern" <stern@rowland.harvard.edu>,
       "USB development list" <linux-usb-devel@lists.sourceforge.net>,
       "Kernel development list" <linux-kernel@vger.kernel.org>
Subject: Re: How should an exit routine wait for release() callbacks?
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On Fri, 13 Apr 2007 13:42:04 +0200,
"Markus Rechberger" <markus.rechberger@amd.com> wrote:

> seems like you have the same problem as the dvb framework has/had.
> 
> http://mcentral.de/hg/~mrec/v4l-dvb-stable
> 
> The last 3 changesets do the trick to not oops, it will delay the 
> deinitialization of the device till the last user closed the device node.

Probably dumb question (since I'm not at all familiar with the dvb
code): Isn't that a different race you're solving there? I don't see
any driver core objects involved (except class devices created by
class_device_create, which obviously don't have the release function
problem). This looks more like a race of "we want an object to go
away, but a user still has a file open" (which would be similar to the
kobject<->sysfs lifetime rules issues, where work is currently ongoing).