Re: [RFC PATCH v3 8/8] vfio: Add nested IOPF support

From: Shenming Lu
Date: Tue Jun 01 2021 - 00:36:21 EST


On 2021/5/27 19:18, Lu Baolu wrote:
> Hi Shenming and Alex,
>
> On 5/27/21 7:03 PM, Shenming Lu wrote:
>>> I haven't fully read all the references, but who imposes the fact that
>>> there's only one fault handler per device?  If type1 could register one
>>> handler and the vfio-pci bus driver another for the other level, would
>>> we need this path through vfio-core?
>> If we could register more than one handler per device, things would become
>> much more simple, and the path through vfio-core would not be needed.
>>
>> Hi Baolu,
>> Is there any restriction for having more than one handler per device?
>>
>
> Currently, each device could only have one fault handler. But one device
> might consume multiple page tables. From this point of view, it's more
> reasonable to have one handler per page table.

Sounds good to me. I have pointed it out in the IOASID uAPI proposal. :-)

Thanks,
Shenming

>
> Best regards,
> baolu
> .