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follow_page_mask code"), GUP(FOLL_SPLIT_PMD) would just have > returned a page. In particular, hugetlb folios that are not PMD-sized > would never have been prone to FOLL_SPLIT_PMD. > > hugetlb folios can be anonymous, and page_make_device_exclusive_one() is > not really prepared for handling them at all. So let's spell that out. Agreed, thanks for fixing. Reviewed-by: Alistair Popple > Fixes: b756a3b5e7ea ("mm: device exclusive memory access") > Cc: > Signed-off-by: David Hildenbrand > --- > mm/rmap.c | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/mm/rmap.c b/mm/rmap.c > index c6c4d4ea29a7..17fbfa61f7ef 100644 > --- a/mm/rmap.c > +++ b/mm/rmap.c > @@ -2499,7 +2499,7 @@ static bool folio_make_device_exclusive(struct folio *folio, > * Restrict to anonymous folios for now to avoid potential writeback > * issues. > */ > - if (!folio_test_anon(folio)) > + if (!folio_test_anon(folio) || folio_test_hugetlb(folio)) > return false; > > rmap_walk(folio, &rwc); > -- > 2.48.1 >