From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Mackerras <paulus@ozlabs.org>
Subject: Re: [PATCH 18/19] KVM: PPC: Book3S HV: add passthrough support
Date: Tue, 22 Jan 2019 16:26:57 +1100
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Cc: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org,
 David Gibson <david@gibson.dropbear.id.au>
To: =?iso-8859-1?Q?C=E9dric?= Le Goater <clg@kaod.org>
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On Mon, Jan 07, 2019 at 08:10:05PM +0100, Cédric Le Goater wrote:
> Clear the ESB pages from the VMA of the IRQ being pass through to the
> guest and let the fault handler repopulate the VMA when the ESB pages
> are accessed for an EOI or for a trigger.

Why do we want to do this?

I don't see any possible advantage to removing the PTEs from the
userspace mapping.  You'll need to explain further.

Paul.