mm: clear pte in clear_soft_dirty()

As mentioned in the commit 56eecdb912 ("mm: Use ptep/pmdp_set_numa()
for updating _PAGE_NUMA bit"), architectures like ppc64 don't do tlb
flush in set_pte/pmd functions.

So when dealing with existing pte in clear_soft_dirty, the pte must be
cleared before being modified.

Signed-off-by: Laurent Dufour <ldufour@linux.vnet.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Laurent Dufour 2015-11-05 18:49:21 -08:00 committed by Linus Torvalds
parent c8f95ed1a9
commit 326c2597a3

View file

@ -792,19 +792,20 @@ static inline void clear_soft_dirty(struct vm_area_struct *vma,
pte_t ptent = *pte;
if (pte_present(ptent)) {
ptent = ptep_modify_prot_start(vma->vm_mm, addr, pte);
ptent = pte_wrprotect(ptent);
ptent = pte_clear_soft_dirty(ptent);
ptep_modify_prot_commit(vma->vm_mm, addr, pte, ptent);
} else if (is_swap_pte(ptent)) {
ptent = pte_swp_clear_soft_dirty(ptent);
set_pte_at(vma->vm_mm, addr, pte, ptent);
}
set_pte_at(vma->vm_mm, addr, pte, ptent);
}
static inline void clear_soft_dirty_pmd(struct vm_area_struct *vma,
unsigned long addr, pmd_t *pmdp)
{
pmd_t pmd = *pmdp;
pmd_t pmd = pmdp_huge_get_and_clear(vma->vm_mm, addr, pmdp);
pmd = pmd_wrprotect(pmd);
pmd = pmd_clear_soft_dirty(pmd);