On Tue, Jan 17, 2017 at 12:01:00PM +0800, Jason Wang wrote: > We allow vhost to clear VIRITO_F_IOMMU_PLATFORM which is wrong since > VIRTIO_F_IOMMU_PLATFORM is mandatory for security. Fixing this by > enforce it after vdc->get_features(). > > Signed-off-by: Jason Wang <jasow...@redhat.com> > --- > hw/virtio/virtio-bus.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/hw/virtio/virtio-bus.c b/hw/virtio/virtio-bus.c > index d31cc00..a886011 100644 > --- a/hw/virtio/virtio-bus.c > +++ b/hw/virtio/virtio-bus.c > @@ -47,6 +47,7 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error > **errp) > VirtioBusState *bus = VIRTIO_BUS(qbus); > VirtioBusClass *klass = VIRTIO_BUS_GET_CLASS(bus); > VirtioDeviceClass *vdc = VIRTIO_DEVICE_GET_CLASS(vdev); > + bool has_iommu = virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM); > > DPRINTF("%s: plug device.\n", qbus->name); > > @@ -63,8 +64,8 @@ void virtio_bus_device_plugged(VirtIODevice *vdev, Error > **errp) > klass->device_plugged(qbus->parent, errp); > } > > - if (klass->get_dma_as != NULL && > - virtio_host_has_feature(vdev, VIRTIO_F_IOMMU_PLATFORM)) { > + if (klass->get_dma_as != NULL && has_iommu) { > + virtio_add_feature(&vdev->host_features, VIRTIO_F_IOMMU_PLATFORM); > vdev->dma_as = klass->get_dma_as(qbus->parent); > } else { > vdev->dma_as = &address_space_memory;
I suspect that's not enough, we must also fail or disable vhost (depending on the options), otherwise things won't work. > -- > 2.7.4