On Wed, 10 Jun 2020 15:11:51 +0200 Pierre Morel <pmorel@xxxxxxxxxxxxx> wrote: > Protected Virtualisation protects the memory of the guest and > do not allow a the host to access all of its memory. > > Let's refuse a VIRTIO device which does not use IOMMU > protected access. > > Signed-off-by: Pierre Morel <pmorel@xxxxxxxxxxxxx> > --- > drivers/s390/virtio/virtio_ccw.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/s390/virtio/virtio_ccw.c b/drivers/s390/virtio/virtio_ccw.c > index 5730572b52cd..06ffbc96587a 100644 > --- a/drivers/s390/virtio/virtio_ccw.c > +++ b/drivers/s390/virtio/virtio_ccw.c > @@ -986,6 +986,11 @@ static void virtio_ccw_set_status(struct virtio_device *vdev, u8 status) > if (!ccw) > return; > > + /* Protected Virtualisation guest needs IOMMU */ > + if (is_prot_virt_guest() && > + !__virtio_test_bit(vdev, VIRTIO_F_IOMMU_PLATFORM)) > + status &= ~VIRTIO_CONFIG_S_FEATURES_OK; > + set_status seems like an odd place to look at features; shouldn't that rather be done in finalize_features? > /* Write the status to the host. */ > vcdev->dma_area->status = status; > ccw->cmd_code = CCW_CMD_WRITE_STATUS;
