From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932084AbbCXWaN (ORCPT ); Tue, 24 Mar 2015 18:30:13 -0400 Received: from g4t3425.houston.hp.com ([15.201.208.53]:36200 "EHLO g4t3425.houston.hp.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752358AbbCXWaI (ORCPT ); Tue, 24 Mar 2015 18:30:08 -0400 From: Jason Low To: linux-mm@kvack.org, linux-kernel@vger.kernel.org, cgroups@vger.kernel.org, Jason Low Cc: Johannes Weiner , Michal Hocko , Christoph Lameter , Linus Torvalds , David Rientjes , Joonsoo Kim , Andrew Morton , "Kirill A. Shutemov" , Aswin Chandramouleeswaran , Christian Borntraeger , Mel Gorman , Hugh Dickins , Minchan Kim , Davidlohr Bueso , Rik van Riel Subject: [PATCH v2 1/2] mm: Use READ_ONCE() for non-scalar types Date: Tue, 24 Mar 2015 15:29:53 -0700 Message-Id: <1427236194-14582-2-git-send-email-jason.low2@hp.com> X-Mailer: git-send-email 1.7.9.5 In-Reply-To: <1427236194-14582-1-git-send-email-jason.low2@hp.com> References: <1427236194-14582-1-git-send-email-jason.low2@hp.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit 38c5ce936a08 ("mm/gup: Replace ACCESS_ONCE with READ_ONCE") converted ACCESS_ONCE usage in gup_pmd_range() to READ_ONCE, since ACCESS_ONCE doesn't work reliably on non-scalar types. This patch also fixes the other ACCESS_ONCE usages in gup_pte_range() and __get_user_pages_fast() in mm/gup.c Signed-off-by: Jason Low Acked-by: Michal Hocko Acked-by: Davidlohr Bueso Acked-by: Rik van Riel Reviewed-by: Christian Borntraeger --- mm/gup.c | 4 ++-- 1 files changed, 2 insertions(+), 2 deletions(-) diff --git a/mm/gup.c b/mm/gup.c index ca7b607..6297f6b 100644 --- a/mm/gup.c +++ b/mm/gup.c @@ -1019,7 +1019,7 @@ static int gup_pte_range(pmd_t pmd, unsigned long addr, unsigned long end, * * for an example see gup_get_pte in arch/x86/mm/gup.c */ - pte_t pte = ACCESS_ONCE(*ptep); + pte_t pte = READ_ONCE(*ptep); struct page *page; /* @@ -1309,7 +1309,7 @@ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, local_irq_save(flags); pgdp = pgd_offset(mm, addr); do { - pgd_t pgd = ACCESS_ONCE(*pgdp); + pgd_t pgd = READ_ONCE(*pgdp); next = pgd_addr_end(addr, end); if (pgd_none(pgd)) -- 1.7.1