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Date: Tue, 6 Jun 2006 15:15:07 -0700
From: Andrew Morton <akpm@osdl.org>
To: Don Zickus <dzickus@redhat.com>
Cc: ak@suse.de, shaohua.li@intel.com, miles.lane@gmail.com, jeremy@goop.org,
       linux-kernel@vger.kernel.org
Subject: Re: [2.6.17-rc5-mm2] crash when doing second suspend: BUG in
 arch/i386/kernel/nmi.c:174
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On Tue, 6 Jun 2006 17:45:53 -0400
Don Zickus <dzickus@redhat.com> wrote:

> On Tue, Jun 06, 2006 at 04:18:15PM +0200, Andi Kleen wrote:
> > 
> > > Because he is using a i386 machine, the nmi watchdog is disabled by
> > > default. 
> > 
> > I changed that - it's now on by default on i386 too.
> > 
> > -Andi
> 
> I am trying to create a patch for this problem and it just dawned on me,
> how does one store the previous state in a suspend/resume path if the code
> hotplugs all the cpus first?  CPU0 is easy because an explicit
> suspend/resume path is called, but it seems to be called last after all
> the other cpus have been removed.  How do I save the state?

I'm really struggling to understand this question.  If you're referring to
some per-cpu state then a CPU hotplug handler would be appropriate?