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Subject: Re: [PATCH -mm] PM: Prevent frozen user mode helpers from failing
	the freezing of tasks (rev. 2)
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Pavel Machek <pavel@ucw.cz>
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       Andrew Morton <akpm@linux-foundation.org>,
       Nigel Cunningham <nigel@nigel.suspend2.net>,
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Date: Tue, 03 Jul 2007 15:31:26 +1000
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On Tue, 2007-06-26 at 10:48 +0200, Pavel Machek wrote:
> > The problem, as far as I understand it, is that the instructions can
> get
> > reordered if there are no barriers in there.
> 
> Are you sure?  I thought atomic variables have barrirers built-in.

bzzzt. they don't.

Ben.