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From: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Date: Fri, 06 Oct 2017 11:53:30 +0200
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Subject: Re: [Qemu-devel] [PATCH 1/2] spapr/rtas: disable the decrementer
 interrupt when a CPU is unplugged
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To: David Gibson <david@gibson.dropbear.id.au>, =?ISO-8859-1?Q?C=E9dric?= Le Goater <clg@kaod.org>
Cc: qemu-ppc@nongnu.org, qemu-devel@nongnu.org, Nikunj A Dadhania <nikunj@linux.vnet.ibm.com>, Alexey Kardashevskiy <aik@ozlabs.ru>

On Fri, 2017-10-06 at 20:07 +1100, David Gibson wrote:
> Hm.  Checking mmu_model doesn't seem right to me.  I mean, it'll get
> the right answer in practice, but the LPCR programming has nothing
> whatsoever to do with the MMU.
> 
> I think explicitly checking if cpu_ is a POWER9 instance with
> object_dynamic_cast would be a better option.

Best is ARCH 300 ... do we hvae arch versions outside of MMU model
these days ?

Ben.