> From: Tian, Kevin <kevin.tian@xxxxxxxxx> > Sent: Thursday, April 27, 2023 2:46 PM > > > 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? This originated from a comment from Eric[1]. At that time, this helper is void type, hence there is no message when there is no devid. Now, this returns 0 if the device is not bound. Maybe checking it in the caller and warn on there? [1] https://lore.kernel.org/kvm/702c2883-1d51-b609-1e99-337295e6e307@xxxxxxxxxx/ Regards, Yi Liu