Re: [PATCH v2 01/11] KVM: arm64: initialize HCRX_EL2

Oliver Upton
2023-06-05T15:42:42Z

On Fri, Jun 02, 2023 at 02:49:50PM +0100, Catalin Marinas wrote:
> On Tue, May 09, 2023 at 03:22:25PM +0100, Kristina Martsenko wrote:
> > ARMv8.7/9.2 adds a new hypervisor configuration register HCRX_EL2.
> > Initialize the register to a safe value (all fields 0), to be robust
> > against firmware that has not initialized it. This is also needed to
> > ensure that the register is reinitialized after a kexec by a future
> > kernel.
> >
> > In addition, move SMPME setup over to the new flags, as it would
> > otherwise get overridden. It is safe to set the bit even if SME is not
> > (uniformly) supported, as it will write to a RES0 bit (having no
> > effect), and SME will be disabled by the cpufeature framework.
> > (Similar to how e.g. the API bit is handled in HCR_HOST_NVHE_FLAGS.)
>
> This looks fine to me but I may have lost track of the VHE/nVHE code
> initialisation paths.
>
> Marc/Oliver, are you ok with this patch (or this series in general)? I'd
> like to merge it through the arm64 tree.

Acked-by: Oliver Upton <oliver.upton@linux.dev>

--
Thanks,
Oliver