From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751678AbdKVOoF (ORCPT ); Wed, 22 Nov 2017 09:44:05 -0500 Received: from mail-by2nam01on0101.outbound.protection.outlook.com ([104.47.34.101]:31501 "EHLO NAM01-BY2-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751329AbdKVOoD (ORCPT ); Wed, 22 Nov 2017 09:44:03 -0500 Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=zi.yan@cs.rutgers.edu; Message-ID: <5A158D22.3040609@cs.rutgers.edu> Date: Wed, 22 Nov 2017 09:43:46 -0500 From: Zi Yan User-Agent: Postbox 5.0.20 (Windows/20171012) MIME-Version: 1.0 To: Michal Hocko CC: Zi Yan , Naoya Horiguchi , Andrew Morton , linux-mm@kvack.org, linux-kernel@vger.kernel.org, Andrea Reale , =?UTF-8?B?SsOpcsO0bWUgR2xpc3Nl?= , stable@vger.kernel.org Subject: Re: [PATCH] mm: migrate: fix an incorrect call of prep_transhuge_page() References: <20171121021855.50525-1-zi.yan@sent.com> <20171122085416.ycrvahu2bznlx37s@dhcp22.suse.cz> <20171122134059.fmyambktkel4e3zq@dhcp22.suse.cz> In-Reply-To: <20171122134059.fmyambktkel4e3zq@dhcp22.suse.cz> X-Enigmail-Version: 1.2.3 Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="------------enig97BB13ED2DB5359A2AEE3BB8" X-Originating-IP: [12.250.207.42] X-ClientProxiedBy: DM5PR13CA0003.namprd13.prod.outlook.com (10.168.112.13) To DM5PR14MB1658.namprd14.prod.outlook.com (10.171.156.16) X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: e34190ba-cba9-4303-55f7-08d531b7782d X-Microsoft-Antispam: UriScan:;BCL:0;PCL:0;RULEID:(5600022)(4604075)(4534020)(4602075)(4627115)(201703031133081)(201702281549075)(2017052603258);SRVR:DM5PR14MB1658; X-Microsoft-Exchange-Diagnostics: 1;DM5PR14MB1658;3:A2iIrGw/wqcQSNKeiXZAPYDUMWbsiwTIW7kwQpatDeN86o187Ov1I/wRGxkIAppZqLy+KPcRPa4WBlhtHRp98caZL39boqdIa6FrQXtRRkE0NgHVoypt9M679s7Z/VJFv4QAdH67Scmj8FVy6Ft3OxQTclQYVDkFYzq/OR852lEDmJqnsjSI0jf+lx9Ck1gGjIIqB23PIhXIAA0bQOcc+GAnJ8MjJ1Cnpr5VX9ZDxXnA0BgpJwJ2pLcMF1SLVnBb;25:ndUxnIQlKck4pR5K1UiT6EaYRBfskBaeY0xgwnUhvN6B0MhnNb4X5IAvFFrQfK0M7TNWevkOWeNUlhaZQJwJr3WlDYJf1+m14Jb4umPpUNZNq+W7N66yJhix0lpIjf/BeLJPfuualJTuAB7+KlpvkjLWcs8nHIKlQneFvtXVIrBz2Q45CH2taRFUW6mFS8T3R2qxidh/2b8s8r1nZ24JunbkURt/TQ1zHMQi5i7HazCiqLmXwVCe018MKE6pjullY2dSRE/vMdD3wxwVf1oQbAc1CbgpOZxGp36M9KGSs+Xd8IXdG6sgFO1cSGPcgc/0c2HlyZAGDBE2eTp5IJlMPw==;31:3Xjhqh0jDOd8KcNGbqhCf9sCaafhAcjyeJPz1GuJUqS8NQdT/NpCwcd2j6jCkQd69/Pb3XazcfYujgrROmV1tTXTqqT1+hRD8kGbS7SaM9veHBQHr82etKeNN0dVCP6m+XXST9hvgYRQ4r0Vmc6jBYhOgd7Wlgasg/ERKQZjP1+YSxEy4ZJgWxWflHDjjm9L82v2r9ne9XFRtzJYY/QbtMU6Z+Iui2dmh11cNGBlDAM= X-MS-TrafficTypeDiagnostic: DM5PR14MB1658: X-Microsoft-Exchange-Diagnostics: 1;DM5PR14MB1658;20: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;4:WfupjaTgaEPARoS2jRNSFzPvBxG5Hl2y0TGKtothr4M8wuqjBFjE4N4oGHcoOfHESLgfBytG/Y3ieKeA8GUacdu5LsuBkrUwwjLUwtipVgKVfmUP0Ruwz8/gh/2g34j03h3zH3jmNr0s8uxExtxaLDbDOR4qQUPA3Py3651iR9RU2ZMBYCRFoiizP3bJg58BvuHQXgX98nP8jEoEIdWuIuktZEegckbPFUgxRWX5W/5eX0iuKG/J6+yOotXDmNPVnMrSoWF++crpLl2lwO56PQ== X-Microsoft-Antispam-PRVS: X-Exchange-Antispam-Report-Test: UriScan:; X-Exchange-Antispam-Report-CFA-Test: BCL:0;PCL:0;RULEID:(100000700101)(100105000095)(100000701101)(100105300095)(100000702101)(100105100095)(11241501159)(6040450)(2401047)(8121501046)(5005006)(93006095)(93001095)(10201501046)(3231022)(100000703101)(100105400095)(3002001)(6041248)(20161123555025)(20161123558100)(20161123560025)(201703131423075)(201702281529075)(201702281528075)(201703061421075)(201703061406153)(20161123562025)(20161123564025)(6072148)(201708071742011)(100000704101)(100105200095)(100000705101)(100105500095);SRVR:DM5PR14MB1658;BCL:0;PCL:0;RULEID:(100000800101)(100110000095)(100000801101)(100110300095)(100000802101)(100110100095)(100000803101)(100110400095)(100000804101)(100110200095)(100000805101)(100110500095);SRVR:DM5PR14MB1658; X-Forefront-PRVS: 0499DAF22A X-Forefront-Antispam-Report: SFV:NSPM;SFS:(10019020)(6009001)(6049001)(376002)(346002)(39860400002)(377424004)(24454002)(189002)(199003)(57704003)(5890100001)(33656002)(97736004)(2906002)(68736007)(16526018)(84326002)(80316001)(786003)(106356001)(81166006)(8676002)(4326008)(90366009)(575784001)(86362001)(105586002)(6486002)(59896002)(88552002)(229853002)(305945005)(7736002)(8656006)(25786009)(42882006)(2950100002)(6916009)(65816999)(53936002)(81156014)(189998001)(83506002)(6246003)(478600001)(49976008)(8936002)(54356999)(76176999)(568964002)(16586007)(16576012)(54906003)(58126008)(66066001)(87266999)(50986999)(6666003)(75432002)(316002)(6116002)(5660300001)(3846002)(21480400003)(101416001)(78286006);DIR:OUT;SFP:1102;SCL:1;SRVR:DM5PR14MB1658;H:[100.72.60.146];FPR:;SPF:None;PTR:InfoNoRecords;MX:1;A:1;LANG:en; X-Microsoft-Exchange-Diagnostics: =?us-ascii?Q?1;DM5PR14MB1658;23:OWbY3EZtSckU/j+UzGtu/kNF+eBQU0ko9qXKyqI1M?= =?us-ascii?Q?ex7Mh2fBGz73/b6XtDHL7bAvvU1Mf1lck3uWRgq4uZ3P8E/I5okx5Ow78LyS?= =?us-ascii?Q?J9CrEpuYfLDYu+AxEV6R7TprxQsKTt44WIJ4UrlS8LlDxSoKrokLD4nSS5p0?= =?us-ascii?Q?HNb1OCk9PO2iFAbxH2hsVnu1Ge5qQPezlyzaRrcRWOKGk05phz6Dz5OILty7?= =?us-ascii?Q?IqhNs16uP6ta9meYPr/kvkSYVS1JENOijWmCx7FnMoSh0PC2dtSpiMcr5ptg?= =?us-ascii?Q?Nhf+NEGaRm+HE1AVqgpfdvdUNxHjAs08tnlLAvg26RG5JwH2yWr2o/KLIOvq?= =?us-ascii?Q?gCdullriTFoTASIhrBBCnMkCMhinNiE2dga/ntm9+U+bdFGISRQJXcsc9aPv?= =?us-ascii?Q?UYFYLxleD6qWvJBEUhoh8foyMxTNfJO8+rQNULgJADkVpfAWvIzDBB1oDuEz?= =?us-ascii?Q?TBmWeEOt1RW3029K0b7VLLfTQF34XzpOdiDrKXsM9yctRvWo+NC8QyO3jQ55?= =?us-ascii?Q?+jU1W+9NF9oRo/NUprMBWsSwNk3J3xwc877wSFUH1q8CQpe95vxtKccO6i+U?= =?us-ascii?Q?VgTe1vbZkHCaTUQ9KBoA0waA15kweirQM286R4lmq+mpLjKvOQBrgnIFtFDF?= =?us-ascii?Q?3wKupa0iqhFv4K4zDwocNedX0V4s+2m0JWzyzM/srbO5QqVxR8VAiK/+tyLD?= =?us-ascii?Q?ObqWRzyqzwSOycFTcgpY3kLWen24x8lMWH+5Tw2flPNKpYIcLL5IGZ4vidIM?= =?us-ascii?Q?f6LVzeBwiwH41l+U8/0GPGhpyH00QcTxzjCeFO55Rxhl9kh8cbZdG/Uejt5w?= =?us-ascii?Q?Ob/jTit1419Y0UXzlou8Xwnk/CVEIsHfai3X56+YYs7fpT3wXPAc3AZG9HHY?= =?us-ascii?Q?j+bxmGG4KF6oz4rZhzsFm+enL7Xiog3JdebiTtk6T3EIeOOJH2FqkYBH/xp7?= =?us-ascii?Q?9xUsRvBXdjxgy1PqDv+Ya1e2dqvHkRqTbMiByje0OCKiC4u6Dl4Ey2kccOdb?= =?us-ascii?Q?Ms/uK7IoN1yB3nrY1HmHxzAeffWjTo/RuE0LjeNDvrODnQu5Dp/o6W4Ojdcc?= =?us-ascii?Q?vtgaoNMYWgMfFNX6/cR2KHMo5F4V2fWh1y+FH2Tj92R8S44IpachI6UeYurA?= =?us-ascii?Q?QMiDx8xXZ1kKdJ+BmXvYqt+2P00to5tWGhMuZsxRlehTjb6mOyer8qYTSvYv?= =?us-ascii?Q?Y7HNivI6gI+he+WTkkGhVPQ7i2IMWoio73Gf4Ux9FtZiXRPemRe75xmEyisO?= =?us-ascii?Q?rz8wwf+MViQahCyYQ3obIYcmu/1X5FAsC+98WLEgBd0XA0mLVi+PZAdOPLUM?= =?us-ascii?Q?KB58797f1vbUikZNo3vvd18joW7nz84R1KDGpchKWghtyDsjErgbV8ZP1Cmm?= =?us-ascii?Q?yzCjqHGkCkFk73Haf4U/NZ6yNf4q1Zi4rFHdHI8fQIaCBxTYaF3J2MLegppb?= =?us-ascii?Q?s17Qwp1hrVMloP4Od+eGCKs35qJmfJd3umDl/DYXsocKqI9Mt4q4WC1lBErI?= =?us-ascii?Q?I65KqtBhxMsq2gciXdicDRN0BEJBpC/wR4eA4TS0J7XcMlObG3bK4Ra?= X-Microsoft-Exchange-Diagnostics: 1;DM5PR14MB1658;6:zkR208b8uU7/gpbdWbh64XeK1PrZlNx63bXlwGU+aq41r9qqaewZLZ22J066UD/zlKRiFT+nmbdajQi41sayngb3Mtf1ozQ947NSTrni6yqEWC6fFWxmYGll5bZUgxjrv7RZrY4UzKPP/iFdyw1RqkM2At6azQRssBpAmOxw4t6GyU+Vl//yRMUs+RfuK08f40ZPk7/zP5XKs6gkBDugXUKTOKakqlqTXBmL8kvDDVg5qiObMg2wxdLQQoN539ODOn3bj4CHUi7IRSoIMGKV+gzXtQYPwmbeyueoXfALlg0KK1FR7NN005B6L0kH27vA7a6lYgBfK7TurjRG5uaL5FhecbR3QDFak4euIt8k5LA=;5:1pe8hcAQmwtggGm7NDEJUWCuhAyt4CIB7bbgQEhDXSI8BhojvlxJ6yhB1Cg72FGwS6aY0Xq3Nhtig3iXo2oxrD0n7JKxD/1N0BYcEHICnYUR/7OfOWsNx6zqqwlRfyaPF3g+rjsZ8SLk0l/Fe0Yn9s2VQ8Swe+ibjGGNGVHXNF4=;24:sw/vUa387nW5Mt5NjDKE6FCjIB+5zZ289LvqmoTIqJVs6DNJvsaAUZp/YYPqwa2SfoiPtsJPl8PKV+y/k+wKzxFcGrRXmpq/MGMNO/8AT0M=;7:8ffrx1nr56DZHB0LEVrsZ7IExXne1qQqP/uypzDPr19ROxKYn1q0H5E3SbL0G8bzZI/fkKXEB3ATP4eHx6i4Hq0OfF4fjK1v6IYYyl/esz8Jhh50B2M2vqMosxMGdd692e7ECQjGrzxj+KmxLboeydckpuJJ+9zce3pqGQuIMq6KYtJMdIwGVg/jzEVmzf1Ii5ismd4Edzs1yCGX/GgpsYMndqVO2x3RTUCVV/da4ViTVdfkTfyTSyPATZDQkE2W SpamDiagnosticOutput: 1:99 SpamDiagnosticMetadata: NSPM X-OriginatorOrg: cs.rutgers.edu X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Nov 2017 14:44:00.0775 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: e34190ba-cba9-4303-55f7-08d531b7782d X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: b92d2b23-4d35-4470-93ff-69aca6632ffe X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR14MB1658 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is an OpenPGP/MIME signed message (RFC 2440 and 3156) --------------enig97BB13ED2DB5359A2AEE3BB8 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Michal Hocko wrote: > On Wed 22-11-17 09:54:16, Michal Hocko wrote: >> On Mon 20-11-17 21:18:55, Zi Yan wrote: > [...] >>> diff --git a/include/linux/migrate.h b/include/linux/migrate.h >>> index 895ec0c4942e..a2246cf670ba 100644 >>> --- a/include/linux/migrate.h >>> +++ b/include/linux/migrate.h >>> @@ -54,7 +54,7 @@ static inline struct page *new_page_nodemask(struct= page *page, >>> new_page =3D __alloc_pages_nodemask(gfp_mask, order, >>> preferred_nid, nodemask); >>> =20 >>> - if (new_page && PageTransHuge(page)) >>> + if (new_page && PageTransHuge(new_page)) >>> prep_transhuge_page(new_page); >> I would keep the two checks consistent. But that leads to a more >> interesting question. new_page_nodemask does >> >> if (thp_migration_supported() && PageTransHuge(page)) { >> order =3D HPAGE_PMD_ORDER; >> gfp_mask |=3D GFP_TRANSHUGE; >> } >=20 > And one more question/note. Why do we need thp_migration_supported > in the first place? 9c670ea37947 ("mm: thp: introduce > CONFIG_ARCH_ENABLE_THP_MIGRATION") says > : Introduce CONFIG_ARCH_ENABLE_THP_MIGRATION to limit thp migration > : functionality to x86_64, which should be safer at the first step. >=20 > but why is unsafe to enable the feature on other arches which support > THP? Is there any plan to do the next step and remove this config > option? Because different architectures have their own way of specifying a swap entry. This means, to support THP migration, each architecture needs to add its own __pmd_to_swp_entry() and __swp_entry_to_pmd(), which are used for arch-independent pmd_to_swp_entry() and swp_entry_to_pmd(). We need this CONFIG_ARCH_ENABLE_THP_MIGRATION before archs that support THP add code for pmd swap entry. --=20 Best Regards, Yan Zi --------------enig97BB13ED2DB5359A2AEE3BB8 Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/ iQEcBAEBCAAGBQJaFY05AAoJEEGLLxGcTqbMgIMH+gL5yfMn4qjZ61tXon+Pd5SZ 2V6ZBz6hHrUr0m/BUleXwaKs6Y6t+9V8VjOz/fEkWLRDxd/IwPKiiJNHJcwjl1Wl l2kM8gGyhiK/zynZM0l+m70yvxCgKwn5alVbUHutokDWYsAW7w4maghFBYdlnojh 2DwdPcqt5AQkFU9MHFvoWKgYSGlCgQq0vVYbleZ91EbokU+rrsvTig94QuU5qH/V Cqdgxrof6U5c0yupjYg+yrt3+W/pfe4IRbVzjHKv7QkeWBq8fUSKiOEM/WolGZ1a 2el2/dasgXJGtyf9OoKZ4mI6T/DUKEn4fx4W80zSLKpcAxz5e7m2HQgKPKQ3c1w= =2We7 -----END PGP SIGNATURE----- --------------enig97BB13ED2DB5359A2AEE3BB8--