On Thu Jan 23, 2025 at 1:46 PM EET, Jarkko Sakkinen wrote: > On Thu Jan 23, 2025 at 12:09 PM EET, Stefano Garzarella wrote: > > On Thu, Jan 23, 2025 at 11:50:40AM +0200, Jarkko Sakkinen wrote: > > >On Wed Jan 22, 2025 at 11:29 PM EET, Dionna Amalie Glaze wrote: > > >> I can appreciate this viewpoint. It even surfaced Microsoft's fTPM > > >> paper to me, which solves some interesting problems we need to solve > > >> in SVSM too. So thanks for that. > > >> > > >> Just to clarify, you're not asking for SVSM to implement the TIS-MMIO > > >> interface instead, but rather to use the fTPM stack, which could make > > >> SVSM calls a TEE device operation? > > > > > >I don't really know what I'm asking because this is barely even a > > >PoC, and I state it like this knowingly. > > > > > >You should make the argument, and the case for the solution. Then > > >it is my turn to comment on that scheme. > > > > I'll check if I can use fTPM, in the meantime I had started to simplify > > this series, avoiding the double stack and exposing some APIs from SEV > > to probe the vTPM and to send the commands. The final driver in > > drivers/char/tpm would be quite simple. > > > > But I'll try to see if reusing fTPM is a feasible way, I like the idea. > > > > > > > >That said, I would not give high odds for acceptance of a duplicate > > >TPM stack succeeding. > > > > Got it ;-) > > > > Thanks to everyone for the helpful feedbacks! > > > > I've been a bit messy these days and I'm in FOSDEM next week, so I hope > > not to take too long for the v2. > > Yeah, OK one thing that I want to say. > > Nail the story. What is it about what is the problem what is the > motivation to solve it etc. If you have all that properly written > up then it is easier to forgive not that well nailed code and > give reasonable arguments. > > And don't rush, I have all the time in the world ;-) Here the point is that if I don't fully understand the context (starting explaining the obvious like what is SVSM) I might give some ridiculously wrong advice. Then people come back to me and start blaming me on saying opposite arguments. I hope you see where I'm standing here. I neither don't want you to do useless and unproductive work. BR, Jarkko
