def METHOD_NAME(self, qemu_devtype, virtio_devid):
    """Check if a modern-only virtio device type behaves as expected"""
    # Force modern mode:
    dev_modern, _ = self.run_device(qemu_devtype,
                                   'disable-modern=off,disable-legacy=on')
    self.assert_devids(dev_modern, pci_modern_device_id(virtio_devid),
                       non_transitional=True)
    # No options: should be modern anyway
    dev_no_opts, ifaces = self.run_device(qemu_devtype)
    self.assertEqual(dev_modern, dev_no_opts)
    self.assertIn('conventional-pci-device', ifaces)
    self.assertIn('pci-express-device', ifaces)