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

On 19 February 2016 at 17:54, Peter Maydell [off-list ref] wrote:

On 19 February 2016 at 16:46, Catalin Marinas [off-list ref] wrote:

quoted

On Fri, Feb 19, 2016 at 03:38:44PM +0000, Peter Maydell wrote:

quoted

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?