mm/hugetlb: use pmd_page() in follow_huge_pmd()

Commit 61f77ed ("mm/hugetlb: reduce arch dependent code around follow_huge_*") broke follow_huge_pmd() on s390, where pmd and pte layout differ and using pte_page() on a huge pmd will return wrong results. Using pmd_page() instead fixes this. All architectures that were touched by that commit have pmd_page() defined, so this should not break anything on other architectures. Fixes: 61f77ed "mm/hugetlb: reduce arch dependent code around follow_huge_*" Signed-off-by: Gerald Schaefer <[email protected]> Acked-by: Naoya Horiguchi <[email protected]> Cc: Hugh Dickins <[email protected]> Cc: Michal Hocko <[email protected]>, Andrea Arcangeli <[email protected]> Cc: Martin Schwidefsky <[email protected]> Acked-by: David Rientjes <[email protected]> Cc: <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
LeeHayun · Apr 14, 2015 · 9753412 · 9753412
1 parent 31f7dc7
commit 9753412
Showing 1 changed file with 1 addition and 2 deletions.
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
@@ -3735,8 +3735,7 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 	if (!pmd_huge(*pmd))
 		goto out;
 	if (pmd_present(*pmd)) {
-		page = pte_page(*(pte_t *)pmd) +
-			((address & ~PMD_MASK) >> PAGE_SHIFT);
+		page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT);
 		if (flags & FOLL_GET)
 			get_page(page);
 	} else {