We have no "end goal". PVNI-ae-udi is intended to capture the semantics of most existing C code. I mention terminology such as "exposure" etc. just because this makes it obvious that this work builds on C's provenance model (the terminology did not exist before as far as I know). PVNI plain is a stricter subset. You can already use it in C and a lot of C code would just work fine with it. Note that some compilers people and formal semantics people were pushing for PVI.

If you think that "map_addr" etc. is an important API, then I agree that this is an innovation on top of what we did. But I personally do not quite see the importance of this API. Yes, it allows some things in the scope of strict provenance which in C would now require PVNI-ae-udi. We envisioned future extensions that prevent exposure of pointers for certain operations, but somehow this seems more academic at this point in time. If you are not using hardware such as CHERI, this does not matter. On the other hand, PVNI-ae-udi makes most existing C code follow a precise provenance model, which I think is a huge step forward.