From: James Houghton <jthoughton@xxxxxxxxxx> commit 63cf584203f3367c8b073d417c8e5cbbfc450506 upstream. By checking huge_pte_none(), we incorrectly classify PTE markers as "present". Instead, check huge_pte_none_mostly(), classifying PTE markers the same as if the PTE were completely blank. PTE markers, unlike other kinds of swap entries, don't reference any physical page and don't indicate that a physical page was mapped previously. As such, treat them as non-present for the sake of mincore(). Link: https://lkml.kernel.org/r/20230302222404.175303-1-jthoughton@xxxxxxxxxx Fixes: 5c041f5d1f23 ("mm: teach core mm about pte markers") Signed-off-by: James Houghton <jthoughton@xxxxxxxxxx> Acked-by: Peter Xu <peterx@xxxxxxxxxx> Acked-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Axel Rasmussen <axelrasmussen@xxxxxxxxxx> Cc: James Houghton <jthoughton@xxxxxxxxxx> Cc: <stable@xxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- mm/mincore.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/mm/mincore.c +++ b/mm/mincore.c @@ -33,7 +33,7 @@ static int mincore_hugetlb(pte_t *pte, u * Hugepages under user process are always in RAM and never * swapped out, but theoretically it needs to be checked. */ - present = pte && !huge_pte_none(huge_ptep_get(pte)); + present = pte && !huge_pte_none_mostly(huge_ptep_get(pte)); for (; addr != end; vec++, addr += PAGE_SIZE) *vec = present; walk->private = vec;
