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=-5.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,NICE_REPLY_A,SPF_HELO_NONE, SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 64721C433ED for ; Tue, 13 Apr 2021 19:24:28 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2C773613C4 for ; Tue, 13 Apr 2021 19:24:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1344598AbhDMTYq (ORCPT ); Tue, 13 Apr 2021 15:24:46 -0400 Received: from mga18.intel.com ([134.134.136.126]:16148 "EHLO mga18.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229458AbhDMTYp (ORCPT ); Tue, 13 Apr 2021 15:24:45 -0400 IronPort-SDR: hQ9PY7ww3vuuG533NQFdj4ayX6yaBbT/VhXeBYfxCnTQEDxygbewUKHjROHmJNjUFZqYSTgmxt JDmiBeFByqag== X-IronPort-AV: E=McAfee;i="6200,9189,9953"; a="181997762" X-IronPort-AV: E=Sophos;i="5.82,220,1613462400"; d="scan'208";a="181997762" Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2021 12:24:19 -0700 IronPort-SDR: 2yoHeovCI3a6lwDX15UkiP+br97TlGA4ZUuiWGsE3zX4jQw45Wy2CkHVPqR70e+/2rirbrrRrU RZUTBeZgmudw== X-IronPort-AV: E=Sophos;i="5.82,220,1613462400"; d="scan'208";a="443539373" Received: from schen9-mobl.amr.corp.intel.com ([10.209.18.184]) by fmsmga004-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 13 Apr 2021 12:24:17 -0700 Subject: Re: [PATCH 2/5] swap: fix do_swap_page() race with swapoff To: "Huang, Ying" , Miaohe Lin Cc: akpm@linux-foundation.org, hannes@cmpxchg.org, mhocko@suse.com, iamjoonsoo.kim@lge.com, vbabka@suse.cz, alex.shi@linux.alibaba.com, willy@infradead.org, minchan@kernel.org, richard.weiyang@gmail.com, hughd@google.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org References: <20210408130820.48233-1-linmiaohe@huawei.com> <20210408130820.48233-3-linmiaohe@huawei.com> <87o8ejug76.fsf@yhuang6-desk1.ccr.corp.intel.com> From: Tim Chen Message-ID: Date: Tue, 13 Apr 2021 12:24:15 -0700 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <87o8ejug76.fsf@yhuang6-desk1.ccr.corp.intel.com> Content-Type: text/plain; charset=windows-1252 Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/12/21 6:27 PM, Huang, Ying wrote: > > This isn't the commit that introduces the race. You can use `git blame` > find out the correct commit. For this it's commit 0bcac06f27d7 "mm, > swap: skip swapcache for swapin of synchronous device". > > And I suggest to merge 1/5 and 2/5 to make it easy to get the full > picture. I'll suggest make fix to do_swap_page race with get/put_swap_device as a first patch. Then the per_cpu_ref stuff in patch 1 and patch 2 can be combined together. Tim