From mboxrd@z Thu Jan  1 00:00:00 1970
From: peter.maydell@linaro.org (Peter Maydell)
Date: Fri, 19 Feb 2016 16:54:17 +0000
Subject: [PATCH v2 0/5] arm64: kernel: Add support for User Access Override
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To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

On 19 February 2016 at 16:46, Catalin Marinas <catalin.marinas@arm.com> wrote:
> On Fri, Feb 19, 2016 at 03:38:44PM +0000, Peter Maydell wrote:
>> This is more of a heads-up than a demand that you Do Something,
>> but perhaps somebody has a clever idea...
>
> Only if Qemu had its own MIDR/REVIDR ;) (and patch the instruction like
> other errata workarounds).

Smiley noted, but FWIW the relevant CPUs advertise themselves as
MIDR 0x411fd070 REVIDR 0 (A57) and MIDR 0x410fd034 REVIDR 0 (A53),
and it should be harmless to patch the ID_AA64MMFR2 read to always
return 0 on any A53 or A57 including h/w, because they'll read as
zero anyway...

So it comes down to how much we want to work around QEMU "errata".

thanks
-- PMM