On 29/10/18 15:48, Peter Maydell wrote: > On 29 October 2018 at 15:40, Marc Zyngier <marc.zyng...@arm.com> wrote: >> My temptation would be not to expose it at all when running on a v7 >> core, and return an error rather than zero. >> >> The other issue is that we currently don't support running 32bit KVM on >> any ARMv8 platform, as we strictly check the CPUs we want to run on (A7 >> and A15). I remember seeing patches that would allow any host core to be >> used (similar to what we have on the 64bit side), but that never made it >> in the tree. > > Ah, that's convenient in some ways. It means we can define the > API to be "for v7, no register available via the ONE_REG API; > for v8, always present", provided we add the constant and the > support before we turn on any actual v8 CPUs for 32-bit KVM > (avoiding the awkward case of "v8 but kernel doesn't expose > MVFR2"). > > I don't think we particularly care about the 32-bit-kvm-on-v8 > part, but it would be good to nail down this wrinkle so we don't > forget about it, maybe ?
Absolutely. I'll write something up. Thanks, M. -- Jazz is not dead. It just smells funny...