On Fri, Feb 05, 2021 at 01:14:11PM -0500, Peter Xu wrote: > But I do have a question on why dax as the only user needs to pass in the > notifier to follow_pte() for initialization. Not sure either, why does DAX opencode something very much like page_mkclean() with dax_entry_mkclean()? Also it looks like DAX uses the wrong notifier, it calls MMU_NOTIFY_CLEAR but page_mkclean_one() uses MMU_NOTIFY_PROTECTION_PAGE for the same PTE modification sequence?? page_mkclean() has some technique to make the notifier have the right size without becoming entangled in the PTL locks.. Jason
