On Sat, Oct 14, 2017 at 01:42:51PM +1100, Paul Mackerras wrote:
> This adds code to make sure that we don't try to access the
> non-existent HPT for a radix guest using the htab file for the VM
> in debugfs, a file descriptor obtained using the KVM_PPC_GET_HTAB_FD
> ioctl, or via the KVM_PPC_RESIZE_HPT_{PREPARE,COMMIT} ioctls.
>
> At present nothing bad happens if userspace does access these
> interfaces on a radix guest, mostly because kvmppc_hpt_npte()
> gives 0 for a radix guest, which in turn is because 1 << -4
> comes out as 0 on POWER processors. However, that relies on
> undefined behaviour, so it is better to be explicit about not
> accessing the HPT for a radix guest.
>
> Signed-off-by: Paul Mackerras <paulus@xxxxxxxxxx>
Applied to my kvm-ppc-next branch.
Paul.
