Reply-To: eric.auger@redhat.com
Subject: Re: [RFC v16 1/9] iommu: Introduce attach/detach_pasid_table API
To:     Lu Baolu <baolu.lu@linux.intel.com>, Joerg Roedel <joro@8bytes.org>
Cc:     peter.maydell@linaro.org, kvm@vger.kernel.org,
        vivek.gautam@arm.com, kvmarm@lists.cs.columbia.edu,
        eric.auger.pro@gmail.com, jean-philippe@linaro.org,
        ashok.raj@intel.com, maz@kernel.org, vsethi@nvidia.com,
        zhangfei.gao@linaro.org, kevin.tian@intel.com, will@kernel.org,
        alex.williamson@redhat.com, wangxingang5@huawei.com,
        linux-kernel@vger.kernel.org, lushenming@huawei.com,
        iommu@lists.linux-foundation.org, robin.murphy@arm.com,
        Jason Gunthorpe <jgg@nvidia.com>
References: <20211027104428.1059740-1-eric.auger@redhat.com>
 <20211027104428.1059740-2-eric.auger@redhat.com>
 <Ya3qd6mT/DpceSm8@8bytes.org>
 <c7e26722-f78c-a93f-c425-63413aa33dde@redhat.com>
 <e6733c59-ffcb-74d4-af26-273c1ae8ce68@linux.intel.com>
From:   Eric Auger <eric.auger@redhat.com>
Message-ID: <fbeabcff-a6d4-dcc5-6687-7b32d6358fe3@redhat.com>
Date:   Wed, 8 Dec 2021 08:33:33 +0100
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Hi Baolu,

On 12/8/21 3:44 AM, Lu Baolu wrote:
> Hi Eric,
>
> On 12/7/21 6:22 PM, Eric Auger wrote:
>> On 12/6/21 11:48 AM, Joerg Roedel wrote:
>>> On Wed, Oct 27, 2021 at 12:44:20PM +0200, Eric Auger wrote:
>>>> Signed-off-by: Jean-Philippe Brucker<jean-philippe.brucker@arm.com>
>>>> Signed-off-by: Liu, Yi L<yi.l.liu@linux.intel.com>
>>>> Signed-off-by: Ashok Raj<ashok.raj@intel.com>
>>>> Signed-off-by: Jacob Pan<jacob.jun.pan@linux.intel.com>
>>>> Signed-off-by: Eric Auger<eric.auger@redhat.com>
>>> This Signed-of-by chain looks dubious, you are the author but the last
>>> one in the chain?
>> The 1st RFC in Aug 2018
>> (https://lists.cs.columbia.edu/pipermail/kvmarm/2018-August/032478.html)
>> said this was a generalization of Jacob's patch
>>
>>
>>    [PATCH v5 01/23] iommu: introduce bind_pasid_table API function
>>
>>
>>   
>> https://lists.linuxfoundation.org/pipermail/iommu/2018-May/027647.html
>>
>> So indeed Jacob should be the author. I guess the multiple rebases got
>> this eventually replaced at some point, which is not an excuse. Please
>> forgive me for that.
>> Now the original patch already had this list of SoB so I don't know if I
>> shall simplify it.
>
> As we have decided to move the nested mode (dual stages) implementation
> onto the developing iommufd framework, what's the value of adding this
> into iommu core?

The iommu_uapi_attach_pasid_table uapi should disappear indeed as it is
is bound to be replaced by /dev/iommu fellow API.
However until I can rebase on /dev/iommu code I am obliged to keep it to
maintain this integration, hence the RFC.

Thanks

Eric
>
> Best regards,
> baolu
>