Gabriel Paubert writes: > But I'm not sure that OOO cannot play tricks on you, what guarantees > that the lwz is done after lwarx?
Nothing, but it doesn't matter, because we have the mm->page_table_lock, and anything that is changing the top 32 bits, or anything in the bottom 32 bits other than the _PAGE_HASHPTE bit, must also take the mm->page_table_lock. The low-level hash_page routine can change the _PAGE_HASHPTE bit without having that lock, which is why we need the atomic sequence. Paul.
