> From: Liu, Yi L <yi.l....@intel.com>
> 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"?
