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Subject: Re: apm_emulation regression
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: "Rafael J. Wysocki" <rjw@sisk.pl>
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Date: Fri, 14 Dec 2007 11:05:12 +1100
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Cc: linuxppc-dev list <linuxppc-dev@ozlabs.org>,
	Johannes Berg <johannes@sipsolutions.net>,
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On Fri, 2007-12-14 at 11:04 +1100, Benjamin Herrenschmidt wrote:
> On Fri, 2007-12-14 at 01:10 +0100, Rafael J. Wysocki wrote:
> > 
> > Hmm.
> > 
> > I'm not that familiar with the APM emulation code, but the description
> > of the
> > problem above suggests that the APM emulation can install a suspend
> > notifier for this purpose.
> 
> It can use the new notifier that happens before freezing yes. Johannes,
> I think that's pretty much what my old powermac implementation did
> (using my private notifier scheme I had there), might be worth reviving
> that bit and sticking it into the generic apm_emu ...

Note that you may want to improve on it with a timeout in case userspace
doesn't ack...

Ben.