From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932305AbbDJAKX (ORCPT ); Thu, 9 Apr 2015 20:10:23 -0400 Received: from TYO202.gate.nec.co.jp ([210.143.35.52]:33972 "EHLO tyo202.gate.nec.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754286AbbDJAKT convert rfc822-to-8bit (ORCPT ); Thu, 9 Apr 2015 20:10:19 -0400 From: Naoya Horiguchi To: Gerald Schaefer CC: Andrew Morton , Hugh Dickins , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , Michal Hocko , Andrea Arcangeli , "Martin Schwidefsky" Subject: Re: [PATCH] mm/hugetlb: use pmd_page() in follow_huge_pmd() Thread-Topic: [PATCH] mm/hugetlb: use pmd_page() in follow_huge_pmd() Thread-Index: AQHQct/9UTSkKG7UaEyC5viKdZ8VSp1EyGEA Date: Fri, 10 Apr 2015 00:08:42 +0000 Message-ID: <20150410000814.GA3623@hori1.linux.bs1.fc.nec.co.jp> References: <1428595895-24140-1-git-send-email-gerald.schaefer@de.ibm.com> In-Reply-To: <1428595895-24140-1-git-send-email-gerald.schaefer@de.ibm.com> Accept-Language: ja-JP, en-US Content-Language: ja-JP X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.128.101.26] Content-Type: text/plain; charset="iso-2022-jp" Content-ID: Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Apr 09, 2015 at 06:11:35PM +0200, Gerald Schaefer wrote: > 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 Thank you for the report. This looks good to me. Acked-by: Naoya Horiguchi > Cc: stable@vger.kernel.org # 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 >