The patch titled Subject: mm: teach mincore_hugetlb about pte markers has been added to the -mm mm-hotfixes-unstable branch. Its filename is mm-teach-mincore_hugetlb-about-pte-markers.patch
This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches...
This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
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------------------------------------------------------ From: James Houghton jthoughton@google.com Subject: mm: teach mincore_hugetlb about pte markers Date: Thu, 2 Mar 2023 22:24:04 +0000
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@google.com Fixes: 5c041f5d1f23 ("mm: teach core mm about pte markers") Signed-off-by: James Houghton jthoughton@google.com Acked-by: Peter Xu peterx@redhat.com Cc: Axel Rasmussen axelrasmussen@google.com Cc: David Hildenbrand david@redhat.com Cc: James Houghton jthoughton@google.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org ---
--- a/mm/mincore.c~mm-teach-mincore_hugetlb-about-pte-markers +++ a/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; _
Patches currently in -mm which might be from jthoughton@google.com are
mm-teach-mincore_hugetlb-about-pte-markers.patch