From mboxrd@z Thu Jan  1 00:00:00 1970
From: Mario Smarduch <m.smarduch@samsung.com>
Subject: Re: [PATCH 3/3] arm, arm64: KVM: handle potential incoherency of
 readonly memslots
Date: Thu, 20 Nov 2014 11:15:54 -0800
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Cc: Laszlo Ersek <lersek@redhat.com>, kvm-devel <kvm@vger.kernel.org>,
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To: Peter Maydell <peter.maydell@linaro.org>
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On 11/20/2014 10:40 AM, Peter Maydell wrote:
> On 20 November 2014 18:35, Mario Smarduch <m.smarduch@samsung.com> wrote:
>> I think beyond consistency, there should be no double mappings with
>> conflicting attributes at any time or CPU state is undefined.
> 
> The situation is not so bleak as this. See section B2.9 "Mismatched
> memory attributes" in the ARMv8 ARM ARM (DDI0487A.d), which lays
> out in some detail what the results of mismatched attributes are
> (generally, you lose ordering or coherency guarantees you might
> have hoped to have). They're not pretty, but it's not as bad
> as completely UNPREDICTABLE behaviour.
> 
> thanks
> -- PMM
> 
Hi Peter,
  thanks for digging that up, quite a list to navigate
but it does provide detailed guidance.

- Mario