Subject: Re: Help needed: Resume problems in 2.6.32-rc, perhaps related to
 preempt_count leakage in keventd
From: Mike Galbraith <efault@gmx.de>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
Cc: Thomas Gleixner <tglx@linutronix.de>, Ingo Molnar <mingo@elte.hu>,
       LKML <linux-kernel@vger.kernel.org>,
       pm list <linux-pm@lists.linux-foundation.org>, Greg KH <gregkh@suse.de>,
       Linus Torvalds <torvalds@linux-foundation.org>,
       Jesse Barnes <jbarnes@virtuousgeek.org>
In-Reply-To: <200911091526.02147.rjw@sisk.pl>
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Date: Mon, 09 Nov 2009 15:44:56 +0100
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On Mon, 2009-11-09 at 15:26 +0100, Rafael J. Wysocki wrote:

> Well, I can add the printk(), but I can't guarantee that I will get the call
> trace once again.  So far I've seen it only once after 20-25 consecutive
> suspend-resume cycles, so ...  you get the idea.
> 
> However, running on a wrong CPU would very nicely explain all of the observed
> symptoms, so I guess we can try a House M.D.-alike approach and assume that the
> answer is "yes, we're running on the wrong CPU".  What would we do next if that
> was the case?

If you're interested in trying a patch, I have a couple that fix things
up here.  My "get a bigger hammer" patch would be best if it's what I
think it is.  If it only fails once in a blue moon though, maybe not
worth even trying.  If I could suspend/resume, I'd try it myself, but I
have (steenking) nvidia card.  No eyecandy or resume for me, though I
can suspend... once.

	-Mike

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