I do like the idea of exporting a couple of helpers that are quite hard
to misuse instead of exporting the variable.
Separate from Dave's question, I wonder if we should open code set_hkid_to_hpa()Yeah, do what's cleanest. This is all super cold code.
inside tdh_phymem_page_wbinvd(). The signature could change to
tdh_phymem_page_wbinvd(hpa_t pa, u16 hkid). set_hkid_to_hpa() is very
lightweight, so I don't think doing it outside the loop is much gain. It makes
the code cleaner.