Design session notes: GPU acceleration in Xen

[Jan Beulich]

On 14.06.2024 18:35, Demi Marie Obenour wrote:
> On Fri, Jun 14, 2024 at 08:38:51AM +0200, Jan Beulich wrote:
>> On 13.06.2024 20:43, Demi Marie Obenour wrote:
>>> 2. Add support for `XEN_DOMCTL_memory_mapping` to use system RAM, not
>>>    just IOMEM.  Mappings made with `XEN_DOMCTL_memory_mapping` are
>>>    guaranteed to be able to be successfully revoked with
>>>    `XEN_DOMCTL_memory_mapping`, so all operations that would create
>>>    extra references to the mapped memory must be forbidden.  These
>>>    include, but may not be limited to:
>>>
>>>    1. Granting the pages to the same or other domains.
>>>    2. Mapping into another domain using `XEN_DOMCTL_memory_mapping`.
>>>    3. Another domain accessing the pages using the foreign memory APIs,
>>>       unless it is privileged over the domain that owns the pages.
>>
>> All of which may call for actually converting the memory to kind-of-MMIO,
>> with a means to later convert it back.
> 
> Would this support the case where the mapping domain is not fully
> priviliged, and where it might be a PV guest?

I suppose that should be a goal.

Jan