Re: [PATCH v4 2/2] s390: virtio: PV needs VIRTIO I/O device protection

[Pierre Morel]

On 2020-07-07 13:14, Michael S. Tsirkin wrote:
> On Tue, Jul 07, 2020 at 11:46:33AM +0200, Cornelia Huck wrote:
> > On Tue,  7 Jul 2020 10:44:37 +0200
> > Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote:
> >
> > > S390, protecting the guest memory against unauthorized host access
> > > needs to enforce VIRTIO I/O device protection through the use of
> > > VIRTIO_F_VERSION_1 and VIRTIO_F_IOMMU_PLATFORM.
> >
> > Hm... what about:
> >
> > "If protected virtualization is active on s390, the virtio queues are
> > not accessible to the host, unless VIRTIO_F_IOMMU_PLATFORM has been
> > negotiated. Use the new arch_validate_virtio_features() interface to
> > enforce this."
>
> s/enforce this/fail probe if that's not the case, preventing a host error on access attempt/

yes, more complete, thanks.

regards,
Pierre

--
Pierre Morel
IBM Lab Boeblingen