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

Commit 61f77eda9b ("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: 61f77eda "mm/hugetlb: reduce arch dependent code around follow_huge_*"
Signed-off-by: Gerald Schaefer <gerald.schaefer@de.ibm.com>
Acked-by: Naoya Horiguchi <n-horiguchi@ah.jp.nec.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Michal Hocko <mhocko@suse.cz>, Andrea Arcangeli <aarcange@redhat.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Gerald Schaefer 2015-04-14 15:42:30 -07:00 committed by Linus Torvalds
parent 31f7dc7969
commit 9753412701

View File

@ -3735,8 +3735,7 @@ retry:
if (!pmd_huge(*pmd)) if (!pmd_huge(*pmd))
goto out; goto out;
if (pmd_present(*pmd)) { if (pmd_present(*pmd)) {
page = pte_page(*(pte_t *)pmd) + page = pmd_page(*pmd) + ((address & ~PMD_MASK) >> PAGE_SHIFT);
((address & ~PMD_MASK) >> PAGE_SHIFT);
if (flags & FOLL_GET) if (flags & FOLL_GET)
get_page(page); get_page(page);
} else { } else {