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Date:   Mon, 25 Sep 2023 14:36:58 +0800
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Subject: Re: [PATCH 6/6] iommu/vt-d: Add domain_alloc_user op
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To:     Baolu Lu <baolu.lu@linux.intel.com>,
        Jason Gunthorpe <jgg@nvidia.com>
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        "Tian, Kevin" <kevin.tian@intel.com>,
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        "Duan, Zhenzhong" <zhenzhong.duan@intel.com>,
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References: <20230919092523.39286-1-yi.l.liu@intel.com>
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From:   Yi Liu <yi.l.liu@intel.com>
In-Reply-To: <ea19494d-8de6-e907-a735-7f2e5f98f9fb@linux.intel.com>
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On 2023/9/21 09:31, Baolu Lu wrote:
> On 9/20/23 9:10 PM, Liu, Yi L wrote:
>>>>> +
>>>>> +    domain = iommu_domain_alloc(dev->bus);
>>>> No need to bounce between core and driver. Just,
>>>>
>>>>     intel_iommu_domain_alloc(IOMMU_DOMAIN_UNMANAGED);
>>>>
>>>> and fully initialize it before return.
>>> If you are going to do that then intel_iommu_domain_alloc() should
>>> fully initialize the domain, not here.
>> I've also considered what Baolu described, but it requires to do some
>> extra initialization which is duplicated with iommu_domain_alloc().
>> So I chose this simple way.
> 
> Okay, got you.
> 
> Once Jason's paging domain and Robin's bus->iommu_ops retirement series
> have landed, the VT-d driver will need some refactoring. Therefore, I'm
> fine with you using a simpler approach here. I'll refactor everything
> later.

yes.

-- 
Regards,
Yi Liu