diff --git a/arch/arm/mm/fault-armv.c b/arch/arm/mm/fault-armv.c index 7a8efe1b37d8..8e9bc517132e 100644 --- a/arch/arm/mm/fault-armv.c +++ b/arch/arm/mm/fault-armv.c @@ -67,6 +67,7 @@ static int do_adjust_pte(struct vm_area_struct *vma, unsigned long address, static int adjust_pte(struct vm_area_struct *vma, unsigned long address) { + spinlock_t *ptl; pgd_t *pgd; pmd_t *pmd; pte_t *pte; @@ -80,11 +81,19 @@ static int adjust_pte(struct vm_area_struct *vma, unsigned long address) if (pmd_none_or_clear_bad(pmd)) return 0; - pte = pte_offset_map(pmd, address); + /* + * This is called while another page table is mapped, so we + * must use the nested version. This also means we need to + * open-code the spin-locking. + */ + ptl = pte_lockptr(vma->vm_mm, pmd); + pte = pte_offset_map_nested(pmd, address); + spin_lock(ptl); ret = do_adjust_pte(vma, address, pte); - pte_unmap(pte); + spin_unlock(ptl); + pte_unmap_nested(pte); return ret; }