On Fri, Apr 8, 2022 at 1:52 AM David Hildenbrand <david@xxxxxxxxxx> wrote: > > On 07.04.22 15:03, Miaohe Lin wrote: > > PageSwapCache is only reliable when PageAnon is true because PG_swapcache > > serves as PG_owner_priv_1 which can be used by fs if it's pagecache page. > > So we should test PageAnon to distinguish pagecache page from swapcache > > page to avoid false-postive PageSwapCache test. > > Well, that's not quite correct. Just because a page is PageAnon() > doesn't mean that it's in the swapache. It means that it might be in the > swapcache but cannot be in the pagecache. > > Maybe you wanted to say > > "So we should test PageAnon() to distinguish pagecache pages from > anonymous pages." Yeah, I agree. The patch looks fine to me with David's comment addressed. > > > > > Signed-off-by: Miaohe Lin <linmiaohe@xxxxxxxxxx> > > --- > > mm/memory-failure.c | 2 +- > > 1 file changed, 1 insertion(+), 1 deletion(-) > > > > diff --git a/mm/memory-failure.c b/mm/memory-failure.c > > index ef402b490663..2e97302d62e4 100644 > > --- a/mm/memory-failure.c > > +++ b/mm/memory-failure.c > > @@ -2262,7 +2262,7 @@ static int __soft_offline_page(struct page *page) > > return 0; > > } > > > > - if (!PageHuge(page) && PageLRU(page) && !PageSwapCache(page)) > > + if (!PageHuge(page) && PageLRU(page) && !PageAnon(page)) > > /* > > * Try to invalidate first. This should work for > > * non dirty unmapped page cache pages. > > > -- > Thanks, > > David / dhildenb > >
