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Subject: Re: [PATCH 0/2] powerpc/xive: fix CPU hot unplug
From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
To: David Gibson <david@gibson.dropbear.id.au>, =?ISO-8859-1?Q?C=E9dric?=
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Cc: linuxppc-dev@lists.ozlabs.org, Michael Ellerman <mpe@ellerman.id.au>,
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Date: Tue, 03 Oct 2017 10:22:40 +0200
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On Tue, 2017-10-03 at 17:58 +1100, David Gibson wrote:
> 
> Ok.. why do you think this isn't of use?  I'm pretty sure this is
> necessary for the TCG case, since MSR is checked in cpu_has_work(),
> which could otherwise wake up the "dead" cpu.

Ony if it's not in a PM state, in that case we check the corresponding
LPCR:PECE* bit. At least on P7 and later.

Cheers,
Ben.