Re: [PATCH v4 0/5] iommu/vt-d: Add page request draining support

[Lu Baolu <baolu.lu@linux.intel.com>]

Hi Kevin,

Thanks a lot for reviewing.

On 2020/5/7 14:38, Tian, Kevin wrote:
>> From: Lu Baolu<baolu.lu@linux.intel.com>
>> Sent: Thursday, May 7, 2020 8:55 AM
>>
>> When a PASID is stopped or terminated, there can be pending PRQs
>> (requests that haven't received responses) in the software and
>> remapping hardware. The pending page requests must be drained
>> so that the pasid could be reused. The chapter 7.10 in the VT-d
>> specification specifies the software steps to drain pending page
>> requests and responses.
>>
>> This includes two parts:
>>   - PATCH 1/4 ~ 2/4: refactor the qi_submit_sync() to support multiple
>>     descriptors per submission which will be used in the following
>>     patch.
>>   - PATCH 3/4 ~ 4/4: add page request drain support after a pasid entry
>>     is torn down.
>>
> I think you should mention that this series depends on Jacob's nested
> SVA series.
> 

Yes. It's based on Jacob's vSVA series since guest unbind also requires
prq draining.

Best regards,
baolu