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Date: Wed, 17 Apr 2013 06:58:20 -0500
From: Robin Holt <holt@sgi.com>
To: "Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>
Cc: Robin Holt <holt@sgi.com>, Ingo Molnar <mingo@kernel.org>,
        Ingo Molnar <mingo@redhat.com>, Russ Anderson <rja@sgi.com>,
        Shawn Guo <shawn.guo@linaro.org>, Oleg Nesterov <oleg@redhat.com>,
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Subject: Re: [Patch -v4 1/4] Migrate shutdown/reboot to boot cpu.
Message-ID: <20130417115820.GF3658@sgi.com>
References: <20130416095827.GJ3672@sgi.com>
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> The get/put_online_cpus() doesn't help in this case, because if a
> hotplug operation is started _after_ this function returns, then
> your task will get force migrated - which makes the get/put_online_cpus()
> pointless. What we need to do is *disable* CPU hotplug altogether.
> We need not even enable it back, since we are rebooting/powering off
> anyway.
> 
> So how about using the following patch in your series and using
> cpu_hotplug_disable() to achieve the goal?

I will incorporate it before my patch and utilize.  Thank you very
much as I was at a loss as to what I should be doing.

Robin