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=-2.6 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,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 F33DEC3A5A7 for ; Wed, 4 Sep 2019 08:14:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id C6D2F22CF7 for ; Wed, 4 Sep 2019 08:14:10 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1567584850; bh=J+OIFYExxocW6B68S4JLGY+p958bcUxgg5CgZpa4dWk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:List-ID:From; b=RchNPbuxLZZuQM2EIobocbeBRzPBmL5GnZ5HWBp6hCmAllFu1Y3eweMhlq4GcaSHx ccyIoQyNVZ8lnTRWwhI7d0nNUNQEw9C1nM0zZ3yvgU9LIxOrOS+lRNdszTKSA2wzCn b0ALd+TCnJ5H43kYStyvE/4h6RepUmCgt4vxngGI= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728797AbfIDIOJ (ORCPT ); Wed, 4 Sep 2019 04:14:09 -0400 Received: from mx2.suse.de ([195.135.220.15]:35076 "EHLO mx1.suse.de" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1725267AbfIDIOJ (ORCPT ); Wed, 4 Sep 2019 04:14:09 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 8A303AB9B; Wed, 4 Sep 2019 08:14:08 +0000 (UTC) Date: Wed, 4 Sep 2019 10:14:08 +0200 From: Michal Hocko To: sunqiuyang Cc: "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" Subject: Re: [PATCH 1/1] mm/migrate: fix list corruption in migration of non-LRU movable pages Message-ID: <20190904081408.GF3838@dhcp22.suse.cz> References: <20190903082746.20736-1-sunqiuyang@huawei.com> <20190903131737.GB18939@dhcp22.suse.cz> <157FC541501A9C4C862B2F16FFE316DC190C1B09@dggeml512-mbx.china.huawei.com> <20190904063836.GD3838@dhcp22.suse.cz> <157FC541501A9C4C862B2F16FFE316DC190C2EBD@dggeml512-mbx.china.huawei.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <157FC541501A9C4C862B2F16FFE316DC190C2EBD@dggeml512-mbx.china.huawei.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Do not top post please On Wed 04-09-19 07:27:25, sunqiuyang wrote: > isolate_migratepages_block() from another thread may try to isolate the page again: > > for (; low_pfn < end_pfn; low_pfn++) { > /* ... */ > page = pfn_to_page(low_pfn); > /* ... */ > if (!PageLRU(page)) { > if (unlikely(__PageMovable(page)) && !PageIsolated(page)) { > /* ... */ > if (!isolate_movable_page(page, isolate_mode)) > goto isolate_success; > /*... */ > isolate_success: > list_add(&page->lru, &cc->migratepages); > > And this page will be added to another list. > Or, do you see any reason that the page cannot go through this path? The page shouldn't be __PageMovable after the migration is done. All the state should have been transfered to the new page IIUC. -- Michal Hocko SUSE Labs