On 03/10/2018 03:40, Wei Yang wrote: > * guest/host writable > * A/D bit is clear, when A/D enabled > > If either one is true, a page fault will be triggered when spte changes. > This means someone else would modify this spte simultaneously. Hi, page faults happen under mmu_lock, with the exception of "fast page fault" that change the accessed and dirty bits. Therefore, neither a concurent present<->nonpresent switch nor a change of spte_has_volatile_bits(old_spte) can happen during mmu_spte_clear_track_bits. Paolo
