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From: Oliver Neukum <oliver@neukum.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Subject: Re: 2.6.21-rc suspend regression: sysfs deadlock
Date: Wed, 7 Mar 2007 19:16:57 +0100
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Am Mittwoch, 7. März 2007 19:02 schrieb Linus Torvalds:
> 
> On Wed, 7 Mar 2007, Oliver Neukum wrote:
> >
> > The problem also exists with unplugging devices. Drivers get no feedback
> > to tell them when it is safe to free the data structures associated with
> > an attribute.
> 
> So you just pointed to *another* data structure that apparently violates 
> the "you MUST use refcounting" rule.
> 
> What is it with you people? It's really simple. Data structures must be 
> refcounted if you can reach them two different ways.
> 
> If you don't use refcounting, then you'd better make sure that the data 
> can be reached only one way (for example, by *not* exposing it for sysfs).
> 
> It really *is* that simple. Read the CodingStyle rules.

Very well, there seems to be no clean way to avoid that work.

	Regards
		Oliver