[PATCH v2 0/5] arm64: kernel: Add support for User Access Override

[Ard Biesheuvel]

On 19 February 2016 at 17:54, Peter Maydell <peter.maydell at linaro.org> wrote:
> On 19 February 2016 at 16:46, Catalin Marinas <catalin.marinas at 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".
>

Doesn't this only affect TCG emulation, and not KVM?