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Yes, the RMM and host are supposed to be aligned on page size, but this means the guest now has this mem_decrypt_granule_size() value that it has to deal with, and it won't always be 4k. The spec introduction of RHI_HOSTCONF_GET_IPA_CHANGE_ALIGNMENT is fixing a defect in earlier RMM specs that just assumed it was always 4k. AFAIK this is unfixable in ARM's architecture.. > Even more, S2 is totally irrelevant here. The only thing that > matters is the host page size vs the guest page size. Nothing else. Yeah Or rather more specifically the RMM now has RHI_HOSTCONF_GET_IPA_CHANGE_ALIGNMENT which says exactly the minimum supported shared/private conversion granule and the VM must obey it. It doesn't actually matter *WHY* the RMM chooses a size, whatever it is the guest must follow it. It would probably be helpful to focus on this a little more, as really this series is implementing a new RMM feature. It is good to explain why this feature was added to RMM in the cover letter, but I would focus the patch commentary on explaining the process of introducing mem_decrypt_granule_size() Jason