Re: [PATCH v2 07/26] iommu/amd: Add support for AMD vIOMMU VF MMIO region

[Jason Gunthorpe <jgg@nvidia.com>]

On Thu, May 28, 2026 at 05:17:19AM +0000, Suravee Suthikulpanit wrote:
> @@ -68,6 +70,16 @@ int amd_iommufd_viommu_init(struct iommufd_viommu *viommu, struct iommu_domain *
>  	aviommu->gid = ret;
>  	pr_debug("%s: gid=%#x", __func__, aviommu->gid);
>  
> +	page_base = amd_viommu_get_vfmmio_addr(iommu, aviommu->gid);
> +
> +	ret = iommufd_viommu_alloc_mmap(&aviommu->core,
> +					page_base, SZ_4K,
> +					(unsigned long *)&data.out_vfmmio_mmap_offset);

This should not be casted like this.

> +	if (ret)
> +		goto err_mmap;
> +
> +	aviommu->vfmmio_mmap_offset = data.out_vfmmio_mmap_offset;
> +
>  	ret = iommu_copy_struct_to_user(user_data, &data,
>  					IOMMU_VIOMMU_TYPE_AMD,
>  					reserved);
> @@ -82,6 +94,8 @@ int amd_iommufd_viommu_init(struct iommufd_viommu *viommu, struct iommu_domain *
>  
>  	return 0;
>  err_init:
> +	iommufd_viommu_destroy_mmap(&aviommu->core, aviommu->vfmmio_mmap_offset);
> +err_mmap:
>  	amd_iommu_gid_free(iommu, aviommu->gid);
>  err_gid:
>  	return ret;
> @@ -100,6 +114,8 @@ static void amd_iommufd_viommu_destroy(struct iommufd_viommu *viommu)
>  	list_del(&aviommu->pdom_list);
>  	spin_unlock_irqrestore(&pdom->lock, flags);
>  	xa_destroy(&aviommu->gdomid_array);
> +	if (aviommu->vfmmio_mmap_offset)
> +		iommufd_viommu_destroy_mmap(&aviommu->core, aviommu->vfmmio_mmap_offset);

I guess mmap_offset could be zero legitimately

Jason