On 2022/3/7 15:42, Huang, Ying wrote: > Muchun Song <songmuchun@xxxxxxxxxxxxx> writes: > >> On Mon, Mar 7, 2022 at 1:22 PM Huang, Ying <ying.huang@xxxxxxxxx> wrote: >>> >>> Miaohe Lin <linmiaohe@xxxxxxxxxx> writes: >>> >>>> When follow_page peeks a page, the page could be reclaimed under heavy >>>> memory pressure >>> >>> I don't think that memory pressure and reclaiming will be an issue. >> >> I think he means a page first to be reclaimed then to be offline >> could encounter this issue and reclaiming is a precondition. > > I don't think reclaiming is a precondition. It seems possible that the > virtual page is migrated, then the physical page is offlined. > What I indeed mean is a page could first be reclaimed, migrated and so on. And then be offlined. Sorry for confusing. Thanks both of you. > Best Regards, > Huang, Ying > >> Thanks. >> >>> >>>> and thus be offlined while it's still being used by the >>>> do_pages_stat_array(). >>> >>> "offline" seems a possible problem. > . >
