From patchwork Tue Jan 12 09:34:58 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dan Williams X-Patchwork-Id: 12012899 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 3B540C433E0 for ; Tue, 12 Jan 2021 09:35:02 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id D0A6C22D58 for ; Tue, 12 Jan 2021 09:35:01 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D0A6C22D58 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 489F28D0080; Tue, 12 Jan 2021 04:35:01 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 43A6F8D0051; Tue, 12 Jan 2021 04:35:01 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 351EE8D0080; Tue, 12 Jan 2021 04:35:01 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0086.hostedemail.com [216.40.44.86]) by kanga.kvack.org (Postfix) with ESMTP id 1EA6D8D0051 for ; Tue, 12 Jan 2021 04:35:01 -0500 (EST) Received: from smtpin17.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DF092180AD81D for ; Tue, 12 Jan 2021 09:35:00 +0000 (UTC) X-FDA: 77696613960.17.bun34_360e35d27514 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin17.hostedemail.com (Postfix) with ESMTP id C3A7E180D0186 for ; Tue, 12 Jan 2021 09:35:00 +0000 (UTC) X-HE-Tag: bun34_360e35d27514 X-Filterd-Recvd-Size: 3972 Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf06.hostedemail.com (Postfix) with ESMTP for ; Tue, 12 Jan 2021 09:34:59 +0000 (UTC) IronPort-SDR: 8nwglWhLyWDFaQXfOZyWkVZmyXMjlMOUF8gD6eBGBATEMwu48XixbVMIl+o5PLHrLFpKbD8ikG USfzjTFNACPw== X-IronPort-AV: E=McAfee;i="6000,8403,9861"; a="175431856" X-IronPort-AV: E=Sophos;i="5.79,341,1602572400"; d="scan'208";a="175431856" Received: from fmsmga005.fm.intel.com ([10.253.24.32]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2021 01:34:58 -0800 IronPort-SDR: 4TSrFpjxdyLfaLml0thLClygScVZvIKkcaXY0+AZZr2Jl3jmQhCIG29P4PmSL8NQX5bZfRWq/5 4B8qgPvs6sjw== X-IronPort-AV: E=Sophos;i="5.79,341,1602572400"; d="scan'208";a="571641600" Received: from dwillia2-desk3.jf.intel.com (HELO dwillia2-desk3.amr.corp.intel.com) ([10.54.39.25]) by fmsmga005-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 12 Jan 2021 01:34:58 -0800 Subject: [PATCH v2 4/5] mm: Fix page reference leak in soft_offline_page() From: Dan Williams To: linux-mm@kvack.org Cc: Andrew Morton , Naoya Horiguchi , David Hildenbrand , Michal Hocko , Oscar Salvador , stable@vger.kernel.org, vishal.l.verma@intel.com, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org Date: Tue, 12 Jan 2021 01:34:58 -0800 Message-ID: <161044409809.1482714.11965583624142790079.stgit@dwillia2-desk3.amr.corp.intel.com> In-Reply-To: <161044407603.1482714.16630477578392768273.stgit@dwillia2-desk3.amr.corp.intel.com> References: <161044407603.1482714.16630477578392768273.stgit@dwillia2-desk3.amr.corp.intel.com> User-Agent: StGit/0.18-3-g996c MIME-Version: 1.0 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: The conversion to move pfn_to_online_page() internal to soft_offline_page() missed that the get_user_pages() reference needs to be dropped when pfn_to_online_page() fails. When soft_offline_page() is handed a pfn_valid() && !pfn_to_online_page() pfn the kernel hangs at dax-device shutdown due to a leaked reference. Fixes: feec24a6139d ("mm, soft-offline: convert parameter to pfn") Cc: Andrew Morton Cc: Naoya Horiguchi Cc: David Hildenbrand Cc: Michal Hocko Cc: Oscar Salvador Cc: Signed-off-by: Dan Williams Reviewed-by: Oscar Salvador Reviewed-by: David Hildenbrand --- mm/memory-failure.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/mm/memory-failure.c b/mm/memory-failure.c index 5a38e9eade94..78b173c7190c 100644 --- a/mm/memory-failure.c +++ b/mm/memory-failure.c @@ -1885,6 +1885,12 @@ static int soft_offline_free_page(struct page *page) return rc; } +static void put_ref_page(struct page *page) +{ + if (page) + put_page(page); +} + /** * soft_offline_page - Soft offline a page. * @pfn: pfn to soft-offline @@ -1910,20 +1916,26 @@ static int soft_offline_free_page(struct page *page) int soft_offline_page(unsigned long pfn, int flags) { int ret; - struct page *page; bool try_again = true; + struct page *page, *ref_page = NULL; + + WARN_ON_ONCE(!pfn_valid(pfn) && (flags & MF_COUNT_INCREASED)); if (!pfn_valid(pfn)) return -ENXIO; + if (flags & MF_COUNT_INCREASED) + ref_page = pfn_to_page(pfn); + /* Only online pages can be soft-offlined (esp., not ZONE_DEVICE). */ page = pfn_to_online_page(pfn); - if (!page) + if (!page) { + put_ref_page(ref_page); return -EIO; + } if (PageHWPoison(page)) { pr_info("%s: %#lx page already poisoned\n", __func__, pfn); - if (flags & MF_COUNT_INCREASED) - put_page(page); + put_ref_page(ref_page); return 0; }