Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753134AbbHJL4R (ORCPT ); Mon, 10 Aug 2015 07:56:17 -0400 Received: from blu004-omc1s14.hotmail.com ([65.55.116.25]:57742 "EHLO BLU004-OMC1S14.hotmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752666AbbHJL4N (ORCPT ); Mon, 10 Aug 2015 07:56:13 -0400 X-TMN: [NzPjedvEQ3vhHp8gMZ91m3+BfSdz0wbC] X-Originating-Email: [wanpeng.li@hotmail.com] Message-ID: From: Wanpeng Li To: Andrew Morton CC: Naoya Horiguchi , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Wanpeng Li Subject: [PATCH v2 2/5] mm/hwpoison: fix PageHWPoison test/set race Date: Mon, 10 Aug 2015 19:28:20 +0800 X-Mailer: git-send-email 1.9.1 In-Reply-To: <1439206103-86829-1-git-send-email-wanpeng.li@hotmail.com> References: <1439206103-86829-1-git-send-email-wanpeng.li@hotmail.com> X-OriginalArrivalTime: 10 Aug 2015 11:56:11.0179 (UTC) FILETIME=[8CD5CFB0:01D0D363] MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1151 Lines: 40 There is a race between madvise_hwpoison path and memory_failure: CPU0 CPU1 madvise_hwpoison get_user_pages_fast PageHWPoison check (false) memory_failure TestSetPageHWPoison soft_offline_page PageHWPoison check (true) return -EBUSY (without put_page) Suggested-by: Naoya Horiguchi Signed-off-by: Wanpeng Li --- mm/memory-failure.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 56b8a71..e0eb7ab 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1704,6 +1704,8 @@ int soft_offline_page(struct page *page, int flags) if (PageHWPoison(page)) { pr_info("soft offline: %#lx page already poisoned\n", pfn); + if (flags & MF_COUNT_INCREASED) + put_page(page); return -EBUSY; } if (!PageHuge(page) && PageTransHuge(hpage)) { -- 1.7.1 -- 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/