[PATCH] mm/hugetlb: use pmd_page() in follow_huge_pmd()

[Gerald Schaefer]

commit 61f77eda "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 commit 61f77eda have pmd_page()
defined, so this should not break anything on other architectures.

Signed-off-by: Gerald Schaefer <gerald.schaefer@xxxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx # v3.12
---
 mm/hugetlb.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index e8c92ae..271e443 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -3865,8 +3865,7 @@ retry:
 	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 {
-- 
2.1.4

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