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Subject: Re: [RFC][PATCH 2/2] PM: Rework handling of interrupts during 
 suspend-resume
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: Arve =?ISO-8859-1?Q?Hj=F8nnev=E5g?= <arve@android.com>
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Date: Fri, 27 Feb 2009 07:57:29 +1100
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On Thu, 2009-02-26 at 12:34 -0800, Arve Hjønnevåg wrote:
> That is enough for drivers that use wakelocks to abort suspend (if I
> fix the wakelock code to not use a platform device as its last abort
> point). It is not enough if you don't have wakelocks, since the
> interrupt can occur after suspend_late has been called and the driver
> has no way to abort suspend.
> 
I still don't quite see how you deal with the race anyway. Ie. Even
without Rafael patch, what if the interrupt occurs after your sysdev
suspend ?

In general, unless they are level sensitive, wakeup interrupts tend to
always be somewhat racy.

Cheers,
Ben.