From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932676AbbCFK1N (ORCPT ); Fri, 6 Mar 2015 05:27:13 -0500 Received: from youngberry.canonical.com ([91.189.89.112]:44588 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933130AbbCFKA2 (ORCPT ); Fri, 6 Mar 2015 05:00:28 -0500 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Naoya Horiguchi , Hugh Dickins , James Hogan , David Rientjes , Mel Gorman , Johannes Weiner , Michal Hocko , Rik van Riel , Andrea Arcangeli , Luiz Capitulino , Nishanth Aravamudan , Lee Schermerhorn , Steve Capper , Andrew Morton , Linus Torvalds , Luis Henriques Subject: [PATCH 3.16.y-ckt 102/183] mm/hugetlb: add migration entry check in __unmap_hugepage_range Date: Fri, 6 Mar 2015 09:56:33 +0000 Message-Id: <1425635874-19087-103-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 2.1.4 In-Reply-To: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> References: <1425635874-19087-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.16 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.16.7-ckt8 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Naoya Horiguchi commit 9fbc1f635fd0bd28cb32550211bf095753ac637a upstream. If __unmap_hugepage_range() tries to unmap the address range over which hugepage migration is on the way, we get the wrong page because pte_page() doesn't work for migration entries. This patch simply clears the pte for migration entries as we do for hwpoison entries. Fixes: 290408d4a2 ("hugetlb: hugepage migration core") Signed-off-by: Naoya Horiguchi Cc: Hugh Dickins Cc: James Hogan Cc: David Rientjes Cc: Mel Gorman Cc: Johannes Weiner Cc: Michal Hocko Cc: Rik van Riel Cc: Andrea Arcangeli Cc: Luiz Capitulino Cc: Nishanth Aravamudan Cc: Lee Schermerhorn Cc: Steve Capper Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Luis Henriques --- mm/hugetlb.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 5aab37914cbd..5f217e906ff9 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -2660,9 +2660,10 @@ again: goto unlock; /* - * HWPoisoned hugepage is already unmapped and dropped reference + * Migrating hugepage or HWPoisoned hugepage is already + * unmapped and its refcount is dropped, so just clear pte here. */ - if (unlikely(is_hugetlb_entry_hwpoisoned(pte))) { + if (unlikely(!pte_present(pte))) { huge_pte_clear(mm, address, ptep); goto unlock; }