mm/thp: use the correct function when updating access flags

We should use pmdp_set_access_flags to update access flags. Archs like powerpc use extra checks(_PAGE_BUSY) when updating a hugepage PTE. A set_pmd_at doesn't do those checks. We should use set_pmd_at only when updating a none hugepage PTE. Signed-off-by: Aneesh Kumar K.V <[email protected]> Cc: Andrea Arcangeli <[email protected]>a Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Benjamin Herrenschmidt <[email protected]>
Kleist · Jun 20, 2013 · 8663890 · 8663890
1 parent 25e33ed
commit 8663890
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
@@ -1265,7 +1265,9 @@ struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,
 		 * young bit, instead of the current set_pmd_at.
 		 */
 		_pmd = pmd_mkyoung(pmd_mkdirty(*pmd));
-		set_pmd_at(mm, addr & HPAGE_PMD_MASK, pmd, _pmd);
+		if (pmdp_set_access_flags(vma, addr & HPAGE_PMD_MASK,
+					  pmd, _pmd,  1))
+			update_mmu_cache_pmd(vma, addr, pmd);
 	}
 	if ((flags & FOLL_MLOCK) && (vma->vm_flags & VM_LOCKED)) {
 		if (page->mapping && trylock_page(page)) {