Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2993640AbbEOXgi (ORCPT ); Fri, 15 May 2015 19:36:38 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:43180 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2992614AbbEOXLB (ORCPT ); Fri, 15 May 2015 19:11:01 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Naoya Horiguchi , Dean Nelson , Andi Kleen , Andrew Morton , Linus Torvalds Subject: [PATCH 3.14 09/51] mm: soft-offline: fix num_poisoned_pages counting on concurrent events Date: Fri, 15 May 2015 16:10:11 -0700 Message-Id: <20150515230950.925338485@linuxfoundation.org> X-Mailer: git-send-email 2.4.0 In-Reply-To: <20150515230950.640453239@linuxfoundation.org> References: <20150515230950.640453239@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1907 Lines: 52 3.14-stable review patch. If anyone has any objections, please let me know. ------------------ From: Naoya Horiguchi commit 602498f9aa43d4951eece3fd6ad95a6d0a78d537 upstream. If multiple soft offline events hit one free page/hugepage concurrently, soft_offline_page() can handle the free page/hugepage multiple times, which makes num_poisoned_pages counter increased more than once. This patch fixes this wrong counting by checking TestSetPageHWPoison for normal papes and by checking the return value of dequeue_hwpoisoned_huge_page() for hugepages. Signed-off-by: Naoya Horiguchi Acked-by: Dean Nelson Cc: Andi Kleen Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- mm/memory-failure.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1723,12 +1723,12 @@ int soft_offline_page(struct page *page, } else if (ret == 0) { /* for free pages */ if (PageHuge(page)) { set_page_hwpoison_huge_page(hpage); - dequeue_hwpoisoned_huge_page(hpage); - atomic_long_add(1 << compound_order(hpage), + if (!dequeue_hwpoisoned_huge_page(hpage)) + atomic_long_add(1 << compound_order(hpage), &num_poisoned_pages); } else { - SetPageHWPoison(page); - atomic_long_inc(&num_poisoned_pages); + if (!TestSetPageHWPoison(page)) + atomic_long_inc(&num_poisoned_pages); } } unset_migratetype_isolate(page, MIGRATE_MOVABLE); -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/