Re: [PATCH v7 9/9] iommu/vt-d: Add iotlb flush for nested domain

Liu, Yi L
2023-12-22T11:59:55Z

> On Dec 22, 2023, at 15:12, Tian, Kevin <kevin.tian@intel.com> wrote:
>
> ﻿
>>
>> From: Liu, Yi L <yi.l.liu@intel.com>
>> Sent: Friday, December 22, 2023 3:02 PM
>>
>>
>>>> On Dec 22, 2023, at 14:47, Tian, Kevin <kevin.tian@intel.com> wrote:
>>>
>>>
>>>>
>>>> From: Yang, Weijiang <weijiang.yang@intel.com>
>>>> Sent: Friday, December 22, 2023 11:56 AM
>>>>> +
>>>>> + xa_for_each(&domain->iommu_array, i, info) {
>>>>> + nested_flush_pasid_iotlb(info->iommu, domain, addr,
>>>> npages, 0);
>>>>> +
>>>>> + if (domain->has_iotlb_device)
>>>>> + continue;
>>>>
>>>> Shouldn't this be if (!domain->has_iotlb_device)?
>>>
>>> yes that is wrong.
>>>
>>> actually it's weird to put domain check in a loop of domain->iommu_array.
>>>
>>> that check along with devtlb flush should be done out of that loop.
>>
>> Maybe adding a bool, set it out of the loop, check the bool in the loop.
>
> the point is that dev iotlb doesn't rely on info->iommu:
>
> nested_flush_dev_iotlb(domain, addr, mask, &fault);
>
> then why do it in the loop of info->iommu?

yes. It should have another device loop instead.