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charset="utf-8" Switch from ptep_get() to ptep_get_lockless() accessor for PTE reads when no lock is taken. Signed-off-by: Alexander Gordeev Acked-by: David Hildenbrand (Arm) Reviewed-by: Lorenzo Stoakes Reviewed-by: Oscar Salvador (SUSE) Reviewed-by: Wei Yang --- mm/page_vma_mapped.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/mm/page_vma_mapped.c b/mm/page_vma_mapped.c index a4d52fdb3056..2ccbabfb2cc1 100644 --- a/mm/page_vma_mapped.c +++ b/mm/page_vma_mapped.c @@ -41,7 +41,7 @@ static bool map_pte(struct page_vma_mapped_walk *pvmw, pm= d_t *pmdvalp, if (!pvmw->pte) return false; =20 - ptent =3D ptep_get(pvmw->pte); + ptent =3D ptep_get_lockless(pvmw->pte); =20 if (pte_none(ptent)) { return false; @@ -183,6 +183,7 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk *= pvmw) struct mm_struct *mm =3D vma->vm_mm; unsigned long end; spinlock_t *ptl; + pte_t pteval; pgd_t *pgd; p4d_t *p4d; pud_t *pud; @@ -310,7 +311,11 @@ bool page_vma_mapped_walk(struct page_vma_mapped_walk = *pvmw) goto restart; } pvmw->pte++; - } while (pte_none(ptep_get(pvmw->pte))); + if (!pvmw->ptl) + pteval =3D ptep_get_lockless(pvmw->pte); + else + pteval =3D ptep_get(pvmw->pte); + } while (pte_none(pteval)); =20 if (!pvmw->ptl) { spin_lock(ptl); --=20 2.51.0