linux-kernel - Re: [PATCH 4/6] iommufd/hw_pagetable: Support allocating nested parent domain

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <7d07bea9-02a5-7113-8cc1-f7aed073cf96@linux.intel.com>
Date:   Wed, 20 Sep 2023 13:05:15 +0800
From:   Baolu Lu <baolu.lu@...ux.intel.com>
To:     Yi Liu <yi.l.liu@...el.com>, joro@...tes.org,
        alex.williamson@...hat.com, jgg@...dia.com, kevin.tian@...el.com,
        robin.murphy@....com
Cc:     baolu.lu@...ux.intel.com, cohuck@...hat.com, eric.auger@...hat.com,
        nicolinc@...dia.com, kvm@...r.kernel.org, mjrosato@...ux.ibm.com,
        chao.p.peng@...ux.intel.com, yi.y.sun@...ux.intel.com,
        peterx@...hat.com, jasowang@...hat.com,
        shameerali.kolothum.thodi@...wei.com, lulu@...hat.com,
        suravee.suthikulpanit@....com, iommu@...ts.linux.dev,
        linux-kernel@...r.kernel.org, linux-kselftest@...r.kernel.org,
        zhenzhong.duan@...el.com, joao.m.martins@...cle.com
Subject: Re: [PATCH 4/6] iommufd/hw_pagetable: Support allocating nested
 parent domain

On 9/19/23 5:25 PM, Yi Liu wrote:
> This extends IOMMU_HWPT_ALLOC to allocate domains used as parent (stage-2)
> in nested translation.
> 
> Signed-off-by: Yi Liu <yi.l.liu@...el.com>
> ---
>   drivers/iommu/iommufd/hw_pagetable.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/iommu/iommufd/hw_pagetable.c b/drivers/iommu/iommufd/hw_pagetable.c
> index 5be7a31cbd9c..26a8a818ffa3 100644
> --- a/drivers/iommu/iommufd/hw_pagetable.c
> +++ b/drivers/iommu/iommufd/hw_pagetable.c
> @@ -83,6 +83,9 @@ iommufd_hw_pagetable_alloc(struct iommufd_ctx *ictx, struct iommufd_ioas *ioas,
>   
>   	lockdep_assert_held(&ioas->mutex);
>   
> +	if ((flags & IOMMU_HWPT_ALLOC_NEST_PARENT) && !ops->domain_alloc_user)
> +		return ERR_PTR(-EOPNOTSUPP);
> +
>   	hwpt = iommufd_object_alloc(ictx, hwpt, IOMMUFD_OBJ_HW_PAGETABLE);
>   	if (IS_ERR(hwpt))
>   		return hwpt;
> @@ -154,7 +157,7 @@ int iommufd_hwpt_alloc(struct iommufd_ucmd *ucmd)
>   	struct iommufd_ioas *ioas;
>   	int rc;
>   
> -	if (cmd->flags || cmd->__reserved)
> +	if (cmd->flags & ~IOMMU_HWPT_ALLOC_NEST_PARENT || cmd->__reserved)
>   		return -EOPNOTSUPP;

Need a parenthesis here, otherwise the compiler will interpret it as a
different condition.

	if ((cmd->flags & ~IOMMU_HWPT_ALLOC_NEST_PARENT) || cmd->__reserved)
		return -EOPNOTSUPP;

Best regards,
baolu