[PATCH v2 00/11] KVM: arm64: Handle the lack of GICv3 exposed to a guest

[Oliver Upton]

On Tue, Aug 27, 2024 at 04:25:06PM +0100, Marc Zyngier wrote:
> It recently appeared that, when running on a GICv3-equipped platform
> (which is what non-ancient arm64 HW has), *not* configuring a GICv3
> for the guest could result in less than desirable outcomes.
> 
> We have multiple issues to fix:
> 
> - for registers that *always* trap (the SGI registers) or that *may*
>   trap (the SRE register), we need to check whether a GICv3 has been
>   instantiated before acting upon the trap.
> 
> - for registers that only conditionally trap, we must actively trap
>   them even in the absence of a GICv3 being instantiated, and handle
>   those traps accordingly.
> 
> - finally, ID registers must reflect the absence of a GICv3, so that
>   we are consistent.
> 
> This series goes through all these requirements. The main complexity
> here is to apply a GICv3 configuration on the host in the absence of a
> GICv3 in the guest. This is pretty hackish, but I don't have a much
> better solution so far.

LGTM, thanks for respinning.

Reviewed-by: Oliver Upton <oliver.upton at linux.dev>

-- 
Thanks,
Oliver