From mboxrd@z Thu Jan  1 00:00:00 1970
From: Paul Mackerras <paulus@ozlabs.org>
Date: Tue, 29 Jan 2019 04:12:41 +0000
Subject: Re: [PATCH 18/19] KVM: PPC: Book3S HV: add passthrough support
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To: =?iso-8859-1?Q?C=E9dric?= Le Goater <clg@kaod.org>
Cc: kvm@vger.kernel.org, kvm-ppc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, David Gibson <david@gibson.dropbear.id.au>

On Mon, Jan 28, 2019 at 07:26:00PM +0100, C=E9dric Le Goater wrote:
>=20
> Is clearing the PTEs and repopulating the VMA unsafe ?=20

Actually, now that I come to think of it, there could be any number of
VMAs (well, up to almost 64k of them), since once you have a file
descriptor you can call mmap on it multiple times.

The more I think about it, the more I think that getting userspace to
manage the mappings with mmap() and munmap() is the right idea if it
can be made to work.

Paul.