On Tue, 14 Jul 2020 13:38:02 +0200 Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote: > 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 > fail probe if that's not the case, preventing a host error on access > attempt. > > Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx> > Acked-by: Halil Pasic <pasic@xxxxxxxxxxxxx> > --- > arch/s390/mm/init.c | 28 ++++++++++++++++++++++++++++ > 1 file changed, 28 insertions(+) (...) > +int arch_validate_virtio_features(struct virtio_device *dev) > +{ > + if (!is_prot_virt_guest()) > + return 0; > + > + if (!virtio_has_feature(dev, VIRTIO_F_VERSION_1)) { > + dev_warn(&dev->dev, > + "legacy virtio not supported with protected virtualizatio\n"); typo: s/virtualizatio/virtualization/ > + return -ENODEV; > + } > + > + if (!virtio_has_feature(dev, VIRTIO_F_IOMMU_PLATFORM)) { > + dev_warn(&dev->dev, > + "support for limited memory access required for protected virtualization\n"); > + return -ENODEV; > + } > + > + return 0; > +} > + > /* protected virtualization */ > static void pv_init(void) > {