Re: [ANNOUNCE] PUCK Agenda - 2024.01.17 - TDP MMU for IOMMU

From: Sean Christopherson
Date: Wed Jan 24 2024 - 12:31:32 EST


On Mon, Jan 22, 2024, Michael Roth wrote:
> On Tue, Jan 16, 2024 at 05:06:44PM -0800, Sean Christopherson wrote:
> > Tomorrow's PUCK topic is utilizing KVM's TDP MMU for IOMMU page tables.
> >
> > FYI, I am currently without my normal internet (hooray tethering), and we're
> > supposed to get a healthy dose of freezing rain tonight, i.e. I might lose power
> > too. I expect to be able to join even if that happens, but I apologize in
> > advance if I end up being a no-show.
> >
> > https://lore.kernel.org/all/20231202091211.13376-1-yan.y.zhao@xxxxxxxxx
> >
> > Time: 6am PDT
> > Video: https://meet.google.com/vdb-aeqo-knk
> > Phone: https://tel.meet/vdb-aeqo-knk?pin=3003112178656
> >
> > Calendar: https://calendar.google.com/calendar/u/0?cid=Y182MWE1YjFmNjQ0NzM5YmY1YmVkN2U1ZWE1ZmMzNjY5Y2UzMmEyNTQ0YzVkYjFjN2M4OTE3MDJjYTUwOTBjN2Q1QGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20
> > Drive: https://drive.google.com/drive/folders/1aTqCrvTsQI9T4qLhhLs_l986SngGlhPH?resourcekey=0-FDy0ykM3RerZedI8R-zj4A&usp=drive_link
> >
> > Future Schedule:
> > January 24th - Memtypes for non-coherent DMA
> > January 31st - Available!
>
> Hi Sean,
>
> I'd like to propose the following topic for the next available slot:
>
> "Finalizing internal guest_memfd APIs needed for SNP (TDX?) upstreaming"
>
> There's 2 existing interfaces, gmem_prepare, gmem_invalidate, that are
> needed by the current SNP patches, and there's some additional background
> about the design decisions here:
>
> https://lore.kernel.org/kvm/20231016115028.996656-1-michael.roth@xxxxxxx/
>
> There's also another gmem interface that you recently proposed for handling
> setting up the initial launch image of SNP guests here that seems like it
> would have a lot of potential overlap with how gmem_prepare is implemented:
>
> https://lore.kernel.org/lkml/ZZ67oJwzAsSvui5U@xxxxxxxxxx/
>
> I'd like to try to get some clarity on what these should look like in order
> to be considered acceptable for upstreaming of SNP, and potentially any
> considerations that need to be taken into account for other users like
> TDX/pKVM/etc.

I penciled this in for the 31st, let me know if that works for you.