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Date: Tue, 6 Dec 2011 11:35:00 +0100
From: Ingo Molnar <mingo@elte.hu>
To: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>, "Rafael J. Wysocki" <rjw@sisk.pl>,
        Thomas Gleixner <tglx@linutronix.de>, H Peter Anvin <hpa@zytor.com>,
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        Tejun Heo <tj@kernel.org>, Borislav Petkov <bp@amd64.org>,
        "Herrmann3, Andreas" <Andreas.Herrmann3@amd.com>
Subject: Re: [PATCH v4 0/7] x86: BSP or CPU0 online/offline
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* Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> wrote:

> > But the hibernation angle should be considered. Hibernation 
> > already has to deal with the case where someone physically 
> > unplugs a CPU and then resumes from the disk image, right? 
> > How does the hibernation code handle that case currently?
> 
> Oh, wait a minute. Are we talking about physical CPU Hotplug 
> in between hibernation and restore? AFAIK, currently we don't 
> handle that at all. [...]

Well, not hotplug, but plain old-fashioned: 'hibernate the box, 
take out a CPU physically and thaw' kind of hardware change.

How will the hibernation code handle this case?

Thanks,

	Ingo