From mboxrd@z Thu Jan 1 00:00:00 1970 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=-11.0 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS 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 0D9D4C433E6 for ; Sun, 17 Jan 2021 22:01:48 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 888C72250E for ; Sun, 17 Jan 2021 22:01:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 888C72250E Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=linux-foundation.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 97F246B02BD; Sun, 17 Jan 2021 17:01:46 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 908676B02BE; Sun, 17 Jan 2021 17:01:46 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7D0356B02BF; Sun, 17 Jan 2021 17:01:46 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0110.hostedemail.com [216.40.44.110]) by kanga.kvack.org (Postfix) with ESMTP id 6191E6B02BD for ; Sun, 17 Jan 2021 17:01:46 -0500 (EST) Received: from smtpin10.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay05.hostedemail.com (Postfix) with ESMTP id 1A621181AF5CC for ; Sun, 17 Jan 2021 22:01:46 +0000 (UTC) X-FDA: 77716639812.10.crush12_350136a27544 Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin10.hostedemail.com (Postfix) with ESMTP id D69B716A4BD for ; Sun, 17 Jan 2021 22:01:45 +0000 (UTC) X-HE-Tag: crush12_350136a27544 X-Filterd-Recvd-Size: 2810 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf48.hostedemail.com (Postfix) with ESMTP for ; Sun, 17 Jan 2021 22:01:45 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id A339920770; Sun, 17 Jan 2021 22:01:43 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1610920904; bh=syw3C+yi+MfIAsKsarxDn5CIv+WBNQ1M+WvC9IOMFT0=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=z9UWtErkwTPaE9iJ/e6FJXucATo+qe58tJGsr8k3lobCCopZfYhtGyFtBlcooJR7H 3MNfOmc3VwhSLYyHiIWqsJ8vJTqMAsaQUBlVrAdJazF72qPbFcDQ38Z9sMFPZD+1q2 ifjtpfMSbB3+cIjwdZ27dFCJ6CcO9Jqk8nbC1GNU= Date: Sun, 17 Jan 2021 14:01:42 -0800 From: Andrew Morton To: Dan Williams Cc: Naoya Horiguchi , Michal Hocko , David Hildenbrand , Oscar Salvador , stable@vger.kernel.org, linux-mm@kvack.org, linux-nvdimm@lists.01.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v4 4/5] mm: Fix page reference leak in soft_offline_page() Message-Id: <20210117140142.ab91797266e0bef6b7dba9f9@linux-foundation.org> In-Reply-To: <161058501210.1840162.8108917599181157327.stgit@dwillia2-desk3.amr.corp.intel.com> References: <161058499000.1840162.702316708443239771.stgit@dwillia2-desk3.amr.corp.intel.com> <161058501210.1840162.8108917599181157327.stgit@dwillia2-desk3.amr.corp.intel.com> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-pc-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit 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: On Wed, 13 Jan 2021 16:43:32 -0800 Dan Williams wrote: > The conversion to move pfn_to_online_page() internal to > soft_offline_page() missed that the get_user_pages() reference taken by > the madvise() path needs to be dropped when pfn_to_online_page() fails. > Note the direct sysfs-path to soft_offline_page() does not perform a > get_user_pages() lookup. > > 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: Michal Hocko > Reviewed-by: David Hildenbrand > Reviewed-by: Oscar Salvador > Cc: > Signed-off-by: Dan Williams A cc:stable patch in the middle is awkward. I'll make this a standalone patch for merging into mainline soon (for 5.11) and shall turn the rest into a 4-patch series, OK?