On Fri, 2024-11-15 at 17:10 +0000, David Hildenbrand wrote: >> [...] >> >> I've talked to Fares internally, and it seems that generally doing >> mm-local mappings of guest memory would work for us. We also figured out >> what the "interrupt problem" is, namely that if we receive an interrupt >> while executing in a context that has mm-local mappings available, those >> mappings will continue to be available while the interrupt is being >> handled. > > Isn't that likely also the case with secretmem where we removed the > directmap, but have an effective per-mm mapping in the (user-space > portion) of the page table? Mh, that's an excellent point, I never thought of that. But with secretmem, the memory would still be protected by SMAP (admittedly, I have no idea how much this is worth in the face of all these speculative issues), right? >> I'm talking to my security folks to see how much of a concern >> this is for the speculation hardening we're trying to achieve. Will keep >> you in the loop there :) > > Thanks! > > -- > Cheers, > > David / dhildenb Best, Patrick
