From mboxrd@z Thu Jan  1 00:00:00 1970
From: peter.maydell@linaro.org (Peter Maydell)
Date: Mon, 15 Sep 2014 12:45:46 -0700
Subject: [PATCH 1/2] ARM: kvm: define PAGE_S2_DEVICE as read-only by
 default
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On 15 September 2014 12:41, Mario Smarduch <m.smarduch@samsung.com> wrote:
> I've been working around the edges of this discussion, and
> maybe be little unclear on this.
>
> But the manuals say intersection of Stage1/Stage2 permissions are
> used. If guest sets stage1 to read-only then setting stage 2
> to read-only or read-write should have no impact. So why
> should stage 2 RW be changed?

Read versus read-write isn't relevant. The point is
that you mustn't let the guest set up a Normal memory
mapping of the same bit of hardware (phys. address
space) that some other guest or the host has set up
as Device mapping.

-- PMM