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>>> +               invlpgb_count_max = (edx & 0xffff) + 1; >> >> I assume the +1 is just a weird undocumented (or weirdly documented) >> encoding? >> https://www.amd.com/content/dam/amd/en/documents/processor-tech-docs/programmer-references/24594.pdf >> says that field InvlpgbCountMax contains the "Maximum page count for >> INVLPGB instruction" and doesn't mention having to add 1 from what I >> can tell. >> > The way I read the documentation, the number > passed in to invlpgb (and retrieved from cpuid) > corresponds to the number of extra pages > invalidated beyond the first page at the specified > address. > > Things have not exploded on me invalidating > multiple pages at once in larger ranges, so I > suspect my reading is right, but it would be > nice for one of the AMD people to confirm :) That is correct. Thanks, Tom >