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

From: Michael Roth
Date: Mon Jan 22 2024 - 14:36:41 EST


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.

Thanks,

Mike

> February - Available!
>