Attestation flow in IBM's s390x

[thomas-fossati]

During the CCC event at FOSDEM, I had a conversation with @steffen-eiden about IBM's s390 attestation flow, and I realised how little I knew about it.

I felt it'd be good to socialize and share information about that with the wider CCC attestation SIG.

Steffen, who has contributed significantly to IBM’s s390x CC implementation, including kernel upstreaming and userland tooling, was eager to share some basic knowledge about the architecture and provide a detailed explanation of the attestation flow.

We discussed dates and he said he'd have the material for a 40-minute presentation ready by the end of March.

[gkostal]

@steffen-eiden - thank you for presenting on 3/26/24. Can you possibly share your slides from the presentation so they can be added to the meeting materials in this repo? You can either submit a PR to this repo, or you can share the slides with me (gkostal_at_microsoft_dot_com), and I can create a PR on your behalf.