Hi Stefano,Julien > On 5 Dec 2022, at 9:43 pm, Stefano Stabellini <sstabell...@kernel.org> wrote: > > On Sat, 3 Dec 2022, Julien Grall wrote: >> On 01/12/2022 16:02, Rahul Singh wrote: >>> This patch series is sent as RFC to get the initial feedback from the >>> community. This patch series consists of 21 patches which is a big number >>> for >>> the reviewer to review the patches but to understand the feature end-to-end >>> we >>> thought of sending this as a big series. Once we will get initial feedback, >>> we >>> will divide the series into a small number of patches for review. >> >> From the cover letter, it is not clear to me what sort of input you are >> expecting for the RFC. Is this about the design itself? >> >> If so, I think it would be more helpful to write an high level document on >> how >> you plan to emulate the vIOMMU in Xen. So there is one place to >> read/agree/verify rather than trying to collate all the information from the >> 20+ patches. >> >> Briefly skimming through I think the main things that need to be addressed in >> order of priority: >> - How to secure the vIOMMU >> - 1 vs multiple vIOMMU >> >> The questions are very similar to the vITS because the SMMUv3 is based on a >> queue. And given you are selling this feature as a security one, I don't >> think >> we can go forward with the review without any understanding/agreement on what >> needs to be implemented in order to have a safe/secure vIOMMU. > > I think we are all aligned here, but let me try to clarify further. > > As the vIOMMU is exposed to the guest, and exposing a queue-based > interface to the guest is not simple, it would be good to clarify in a > document the following points: > > - how is the queue exposed to the guest > - how are guest-inputs sanitized > - how do the virtual queue resources map to the physical queue > resources > - lifecycle of the resource mappings > - any memory allocations triggered by guest actions and their lifecycle > > It is difficult to extrapole these details from 21 patches. Having these > key detailed written down in the 0/21 email would greatly help with the > review. It would make the review go a lot faster.
Ack. I will send the design docs by next week that will include all the requested information. Regards. Rahul
