> From: Yi Liu > Sent: Wednesday, April 26, 2023 10:54 PM > + > +/* > + * Return devid for devices that have been bound with iommufd, > + * returns 0 if not bound yet. > + */ > +u32 vfio_iommufd_physical_devid(struct vfio_device *vdev) > +{ > + if (WARN_ON(!vdev->iommufd_device && !vdev->iommufd_access)) > + return 0; is WARN_ON too restrictive?