diff --git a/drivers/vfio/pci/vfio_pci_core.c b/drivers/vfio/pci/vfio_pci_core.c
index fa168b434239..3f139360752e 100644
--- a/drivers/vfio/pci/vfio_pci_core.c
+++ b/drivers/vfio/pci/vfio_pci_core.c
@@ -2235,7 +2235,7 @@ int vfio_pci_core_register_device(struct vfio_pci_core_device *vdev)
 		return -EBUSY;
 	}
 
-	if (pci_is_root_bus(pdev->bus)) {
+	if (pci_is_root_bus(pdev->bus) || pdev->is_virtfn) {
 		ret = vfio_assign_device_set(&vdev->vdev, vdev);
 	} else if (!pci_probe_reset_slot(pdev->slot)) {
 		ret = vfio_assign_device_set(&vdev->vdev, pdev->slot);