> From: Liu, Yi L <yi.l.liu@xxxxxxxxx> > Sent: Wednesday, March 8, 2023 9:29 PM > + > +static int vfio_device_cdev_probe_noiommu(struct vfio_device *device) > +{ > + struct iommu_group *iommu_group; > + int ret = 0; > + > + if (!IS_ENABLED(CONFIG_VFIO_NOIOMMU) || !vfio_noiommu) > + return -EINVAL; > + > + if (!capable(CAP_SYS_RAWIO)) > + return -EPERM; > + > + iommu_group = iommu_group_get(device->dev); > + if (!iommu_group) > + return 0; > + > + /* > + * We cannot support noiommu mode for devices that are protected > + * by IOMMU. So check the iommu_group, if it is a no-iommu group > + * created by VFIO, we support. If not, we refuse. > + */ > + if (!vfio_group_find_noiommu_group_from_iommu(iommu_group)) > + ret = -EINVAL; > + iommu_group_put(iommu_group); > + return ret; can check whether group->name == "vfio-noiommu"?