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 Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 62D70D25030 for ; Mon, 12 Jan 2026 01:37:23 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 65D0D6B0088; Sun, 11 Jan 2026 20:37:22 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 6142F6B0089; Sun, 11 Jan 2026 20:37:22 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 494756B008A; Sun, 11 Jan 2026 20:37:22 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 366826B0088 for ; Sun, 11 Jan 2026 20:37:22 -0500 (EST) Received: from smtpin30.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id D8604D25EF for ; Mon, 12 Jan 2026 01:37:21 +0000 (UTC) X-FDA: 84321599082.30.18D5B2D Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.9]) by imf24.hostedemail.com (Postfix) with ESMTP id 9731718000A for ; Mon, 12 Jan 2026 01:37:17 +0000 (UTC) Authentication-Results: imf24.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b="nH7zvb/N"; spf=pass (imf24.hostedemail.com: domain of matthew.brost@intel.com designates 198.175.65.9 as permitted sender) smtp.mailfrom=matthew.brost@intel.com; dmarc=pass (policy=none) header.from=intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1768181838; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=fKiuIkVUWocTlml1ph9fZVzEIa62kZGhU4b2pmeLwx0=; b=K4dNQA8y9TVDV48TCaUrSLuMofjTEzNc9PyViliudrCoOA1FZ9W+RZocjo330TdY/J3IKV jix4vVj+7hquXjO/sSQYeUALohalS+n1NWo8/hY5g4IoHQJr33R5U44dJQ4QXi0PYBD98M UVU/QUQMn39ce1wOfhZLEZhDqdFJ78o= ARC-Authentication-Results: i=2; imf24.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b="nH7zvb/N"; spf=pass (imf24.hostedemail.com: domain of matthew.brost@intel.com designates 198.175.65.9 as permitted sender) smtp.mailfrom=matthew.brost@intel.com; dmarc=pass (policy=none) header.from=intel.com; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}") ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1768181838; a=rsa-sha256; cv=fail; b=bbiQtFF9zlgXDJINprIyYTc8t1uWmwGavl98W0qX2u+5VWfEkUBYZ9wi2Vy8b8UMK9zjQQ X2nEQLw6rLI6yJhoDsQAiR523Z2V86sx2Gl3/rWqrtmdssToQFIlOLGuyPyEJRSdqVjeYd YO0OoED73RVNUIM9LWmh5HaiFGODol4= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1768181838; x=1799717838; h=date:from:to:cc:subject:message-id:references: content-transfer-encoding:in-reply-to:mime-version; bh=OHSLaMopdyW4jwuOos94UG6fkLZJ4B+5pHRmeiaqeBI=; b=nH7zvb/NCIdeSfvlBOtbTDL7UsqdhL/M1Yw3BGaOyx5iRRjHe1hzs9Ks yt/O0ykyVCA0v2lDPvhNXL5wZ+Ya+gLB+g+nSOaxnubaADMt7SjdnETxX Z7MskHBS6Ovim3Swewe92IJ2QGUZe+ofxe6SvE8hJRArmDd8ih2yI+Icr TjzNyAgcVZzQ2javreyNf73oJe9Cm48XgOvO8FEsjQ/FWFtOkBVvgpcSq eddmFg1+i4sinC6qOcyw8sDE/pHqdGVcxJFw9jrc52bDPfcVHlzsYn/Op 36hwrm7sRrHwsSB0zrZGmClLyf88ji7AcSqBL22vspSut4RF+gt5dbaV7 w==; X-CSE-ConnectionGUID: tVVXPHerRrOtPGH3FEe0Uw== X-CSE-MsgGUID: 01nDwADSTmGwwaCKWK+BmQ== X-IronPort-AV: E=McAfee;i="6800,10657,11668"; a="92123159" X-IronPort-AV: E=Sophos;i="6.21,219,1763452800"; d="scan'208";a="92123159" Received: from orviesa010.jf.intel.com ([10.64.159.150]) by orvoesa101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2026 17:37:15 -0800 X-CSE-ConnectionGUID: sD8gkpGPT+m7AvzAv4izKA== X-CSE-MsgGUID: DFvxbuSrTf6A68eFN/Nhrg== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.21,219,1763452800"; d="scan'208";a="203175424" Received: from fmsmsx903.amr.corp.intel.com ([10.18.126.92]) by orviesa010.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 11 Jan 2026 17:37:15 -0800 Received: from FMSMSX903.amr.corp.intel.com (10.18.126.92) by fmsmsx903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29; Sun, 11 Jan 2026 17:37:14 -0800 Received: from fmsedg902.ED.cps.intel.com (10.1.192.144) by FMSMSX903.amr.corp.intel.com (10.18.126.92) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29 via Frontend Transport; Sun, 11 Jan 2026 17:37:14 -0800 Received: from PH8PR06CU001.outbound.protection.outlook.com (40.107.209.47) by edgegateway.intel.com (192.55.55.82) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.29; Sun, 11 Jan 2026 17:37:14 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=xBe0sISNMk+6MqudxgMAwJfqsUJMMjG/WxaFBHweui3prBPktFlBY7M8IN3Izuey8eBAFa1H+pO5NddDFl7aulQIAPoUqHwroALwfbkKAPtNcHFBCIFno6OgxXACogBWDAiQFnS9QyLWkCypNr0k4Fu2JnSd+sKUDubHQkDydlkXRxY0dDN2n8usF7ZB6yP1NBV0rw23nRDnrHBMkymE7Da1rbm0ezAfGf1st7w/6ghO6WxlNtl9rBcYwJ7Ah/zO4R1EyZcSW+b+Y32CTnqnj9WpKtWvfjJfcoDwW3lx4m03gFhX8RDPWem7Sxy+r6DvjSMAVFF2Mi2s6FIXtV5Jww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=fKiuIkVUWocTlml1ph9fZVzEIa62kZGhU4b2pmeLwx0=; b=Ya18HGI2fSOUBWodC9nEz9d3rskTeTX0J0kHny0S3xjQtg3Rvu/P3c23vBmdcaJct5Yh9LobKaYzxxe2rcw3Dkx6YeDTIHn8HBxJEYrIPNPHqyXd4F/uglEoIBi0bWv80edMqMskugUcjPjmJy+Ttl1np1nvJGwupfE+wIOU11jG3AusAbs3AoD8Z2TeH7AJJ+IDQ9TF/whvGDyJIE7MxsEm/o7HRodk50wgAPZthn6NeY8uoiGxrzXuMm15+8EzbCMg/e3xgT71fNmfKYDgRf4MT8V36Aoo5I3KlVn7wbCgKd19slgr+ZB+NHV6k9eiO5rRRyMq+h10GVwcmdJMNw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Received: from PH7PR11MB6522.namprd11.prod.outlook.com (2603:10b6:510:212::12) by PH0PR11MB4999.namprd11.prod.outlook.com (2603:10b6:510:37::6) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9499.7; Mon, 12 Jan 2026 01:37:12 +0000 Received: from PH7PR11MB6522.namprd11.prod.outlook.com ([fe80::9e94:e21f:e11a:332]) by PH7PR11MB6522.namprd11.prod.outlook.com ([fe80::9e94:e21f:e11a:332%7]) with mapi id 15.20.9456.015; Mon, 12 Jan 2026 01:37:12 +0000 Date: Sun, 11 Jan 2026 17:37:08 -0800 From: Matthew Brost To: Zi Yan CC: Matthew Wilcox , Balbir Singh , Francois Dugast , , , "Madhavan Srinivasan" , Nicholas Piggin , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Felix Kuehling , Alex Deucher , Christian =?iso-8859-1?Q?K=F6nig?= , David Airlie , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Thomas Zimmermann , Lyude Paul , Danilo Krummrich , "Bjorn Helgaas" , Logan Gunthorpe , "David Hildenbrand" , Oscar Salvador , "Andrew Morton" , Jason Gunthorpe , "Leon Romanovsky" , Lorenzo Stoakes , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Alistair Popple , , , , , , , , Subject: Re: [PATCH v4 1/7] mm/zone_device: Add order argument to folio_free callback Message-ID: References: <20260111205820.830410-1-francois.dugast@intel.com> <20260111205820.830410-2-francois.dugast@intel.com> <874d29da-2008-47e6-9c27-6c00abbf404a@nvidia.com> <0D532F80-6C4D-4800-9473-485B828B55EC@nvidia.com> Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <0D532F80-6C4D-4800-9473-485B828B55EC@nvidia.com> X-ClientProxiedBy: SJ0PR03CA0135.namprd03.prod.outlook.com (2603:10b6:a03:33c::20) To PH7PR11MB6522.namprd11.prod.outlook.com (2603:10b6:510:212::12) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: PH7PR11MB6522:EE_|PH0PR11MB4999:EE_ X-MS-Office365-Filtering-Correlation-Id: ef7738e6-33a6-424c-c9e0-08de517b1be9 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|7416014|376014|366016; X-Microsoft-Antispam-Message-Info: =?utf-8?B?R09GK1haUFZtQkU0T2IvYXIzL2ZXSVY3OGlRaFFwb3dnWFA0YVY1R2duVjNJ?= =?utf-8?B?Z2ZnZk9ScUpBSzVrQ25oWmlnc1AvTDFJdkFCbFQ1YnVQRVdaR1pEdDgzc1JD?= =?utf-8?B?WW5TVEpJaGw3VTdLRmUxRWcwQjFnY2JVcFZ4dkUxMEVDZzJJOFprcG1JRC8y?= =?utf-8?B?MUc5bUxXTDZmRFBuTHNCYU1CeHdTeGxHN1p0RDJReDdJK0d6TGJDYkZ3KzNj?= =?utf-8?B?Q0tPbFVXUTc1WjJHTEhZcGM1M3VDbDVCUEdEVTRCTnkzTjRIQjNXNzlHeVpE?= =?utf-8?B?MzJjanZkL2RhaXl5d1c4R2NrMUJWU3BVZDVwT3VOelAwOVk5djk0T3A0ZDV0?= =?utf-8?B?NmpabGZHZHVwUXRXd1JNNWJwV1grdlZpK3NkcUxIYnB3ZzB5MU1PVjQycFNH?= =?utf-8?B?M0kxckEybDIrYmxITjU2NVNPdEJLWEgvL3pOb0loUUwwUFVEdkhMQ0NqbEQ5?= =?utf-8?B?aWZlUmUrYjdMSWZpUWo1aDZBa1FDWC9VVE96VUcxWUZlZlplNE9SbGkvM241?= =?utf-8?B?ZnV6Vi9FY1I1ZjNUZDczN3BSWURKOWpBTC9meThyUXgvQjc5Zm9BUjhnNVgw?= =?utf-8?B?NFlmVWszNEZ3RzBsbzFyc0pqbGRsNmhJTmM3dlRYVWxCY0pXL3pSeDN3VGhz?= =?utf-8?B?VFA5NEhpK3lacjM2V01RckhmRHZLeWltRWtVbC9YcDd2M2RqRU5wbGRaWmlp?= =?utf-8?B?Mi9XN1NYRnpkM1RpNXhDWjV0dXdUejI4QzZhVm9ldkxwaWZQSFJJMHFtRUoy?= =?utf-8?B?c094RnROcXNjTVpXMllzTWFzcEo2N1NleHpTd2Q3dUJ6anNET1duY1FVaHly?= =?utf-8?B?NlBXYXZhbkZFLzM5WWdwcUdUMnRtSW43VHE5cjV6R0hWRmE1VlRvUytGamdx?= =?utf-8?B?VCsxdkpzTlhzaG5lK2t2TWFrYlZGVjBlN2xaOVFia0dUSVl2ZkVFWmNVZHpH?= =?utf-8?B?ajVRM2JsTkRRR1Q3UGl2NlY5dEQyZmYzbFplYkNVYlZIU0ZibXR6RHZOOFli?= =?utf-8?B?ZFcxZHNXQUhMQldITTRKekw3TTQvTFQyM0xLTlBPeUx2RVdPUDU3TjVEZXkw?= =?utf-8?B?eXZZSlc0a3dXNTVBekdLVGFBbnFROUM4VS9VaTY1VUJhMzlvY3JUVTR3ZWVi?= =?utf-8?B?cE1aZm12VmFYV0dVWmt4cExubVcvSnR1R1F4UG5PMVlQUmllNThNQ0MydGpp?= =?utf-8?B?ZkV2d29uTVpESmEyM2M2VFZNN1AzR0RWdDNxbXRINk9VYWNlSHJicExHcnUw?= =?utf-8?B?bndhZFJVZTFFU2tlSHZ5dENieGl6cFVod3ZrTXB1UTVjUWpZY0JEQUtpK3ZT?= =?utf-8?B?SUdiamRWQVFFbmhnVG9DcHp3QXhPaXZraHEzNzJOZWVrVlZUdHBwM2NtamFh?= =?utf-8?B?bXFIQXBhTlMyaG1MbWF3bWpMbFFBZzV4WW44Qlh6Smd0L1g0KzZRU0lYeklx?= =?utf-8?B?ZG9CVWxxVTYwckM1Z3M3dHlCQ1JiNlVRWmYzcFJ1dlVUVHhrbXpFK3JKMHVX?= =?utf-8?B?Z2VTa04wWkFEZWJXM3J2S0RZd3BENXFhV28zNElnOHRWZ2xtcUcyMHF6cE5k?= =?utf-8?B?VEl0YUl1ZjA1RlFMYXcyOTRSLzNOc0xYZVVlOUdSMVRzNnNWMXJNeStlOXNC?= =?utf-8?B?RDhqQU40OGxtdnlWVTk0Qno3bGV6Z3llTDFWRHR4bHJnRWxIV3ZUeUl3K05V?= =?utf-8?B?YkdYdjRza3BvMXJjSERqRUwvRWdiN01aMlY0R1NyU0JDclhpZThRMlFYQkp5?= =?utf-8?B?SUNqdnJ3RWpPS0tmYU1zR2NZZzN4UnoxK0pQZS9wREJRUFJGZjY3N3lOVWxG?= =?utf-8?B?Qy8zUnZMZGpnWk5JMUZISXpYMFczTG9WbnptQlVZb3dUd1lYQ1JuTUVnWG5L?= =?utf-8?B?Yzl4cjBLaVc0OWp2RUJQckxUUm9IemE5NFFkbnZQbHlld3F5K2Y1UklROGxE?= =?utf-8?Q?zlho09rB1LhmB5x145I+j/zXB7wLQXtf?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:PH7PR11MB6522.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(7416014)(376014)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?dWs4WjhKTDZGZC96aEFmS3ZYTXdXcHZhZGxoaDVtRWlxdHJROXVlVWdnS3Bv?= =?utf-8?B?d1I0aWZ5UFQ1TFBmSkRLdTJFMVhzeGNnWUVZKytGSlNhNnczUElXR3I5bVFO?= =?utf-8?B?RFBNNDc2eEptNFJ2YnFlTlJxQzJjb2dkc1JsQVkxNS9pWWFZSlNZdlNPMzBP?= =?utf-8?B?ZG8rTjZLQzN5aE5CTStXWjhUb3IyWUZsd2ZxMTVmeS9yYXFzaVUyR2xXWXA1?= =?utf-8?B?UW9POFY1Uk9tUEt4Z2RmV0lRKzNHbEhQdGtVTlVTYzBDZXhJUTlUNmFIL0dJ?= =?utf-8?B?VCt2eVJxZ1l6VFpVZmlhMlUrZGFaZWNsWUNUMVphT1Rhb0VRU29pV2pNZlRx?= =?utf-8?B?VEhNOFZ2bW90Q24zOGJvQ25RanlSQzBpZTQrNXZRbnV1dm5QL091OW05MERs?= =?utf-8?B?K1NoMGxYRVo1UkFxNWlHUFNhQUpIaXAwWW0ySlJKNnBKZUJPa3BFd0c2V1lT?= =?utf-8?B?TlAxSUdYVkk5TkpLNWc1MVIyaFBjN2dMSEJkeGVLQ1ZCZTcyei9xT2toak5B?= =?utf-8?B?Mm9wUTQ2aXFiR1BxMFk0dGtsL0QycjYvZTlqeGVPV2Joa2IrbjNIelRNejZM?= =?utf-8?B?bDloeDQ3cWx6dWdpVjdQTWk2Q3NEWG9JZDRSemFsd050YjJzUDNIUXp6eFJG?= =?utf-8?B?S1dGZUFJT1ljbVVjMlc3VzNqL0cvZmd2MjZEbHNYQUlmUFhNcnZLOEJxdkpK?= =?utf-8?B?OXRXWlRLb1pkTTVNZU91UmEzNE5uMUdUeTlWZ0NFQWZLUU9uWUd5cEYyd1VJ?= =?utf-8?B?RGNlWUNJeU9sVmM2ZzZMZERkQmV5T2hIWXhoQjgzOGZOZUs3cnpqRWhkM2l6?= =?utf-8?B?cnYvbXVrakFIUzh5WmR6dDFNay9OMzBvdFp0STF1OG0wd1NVck9HOWxuVmlX?= =?utf-8?B?VE1SV1pzOGpwVkpPVGV0cXBaZWUxbVRTRVVlbVBQejc5ZjEwb1lkdGNTbUtv?= =?utf-8?B?Q2V2WjM2Q3ZpV3dFSWRIQ0M5T2dGQjZMZjRQSndGMjJjUkk2Vk1UMURMRUY3?= =?utf-8?B?SFR0U1p3SElmMFJOcTkxZFVIMUU1eHBDTXZTRWZkS3ZiUkNGUDdKaWsrWXh3?= =?utf-8?B?VHpKQVZIK2tKbnN3MUFnNmZIc0Z2cU1VWi9GUkFCQnk1VGRoZStSVUtVZEJt?= =?utf-8?B?QWlZQlJTN1VZdmZTaEE1MGJqb0MrdHgrNkRmYXUvS2FSZFdKc1RTVWVmajVT?= =?utf-8?B?UStXTlZhVHFaOXkyYkN6TnVNd1Y0Z3gxN1BTS1p5dlhTQjNTRUpsRWtmTzBD?= =?utf-8?B?TmJxYy9QTkpPaCsveWk2UEZXTDZzRFloZncyUWRSUFNDd3ZscnhocGZuc25W?= =?utf-8?B?UmxFY2RPdG9jbnViMitTN1FtRVdSbDlJVDg1WFFrV05leThvSndmQ3ZpUFg5?= =?utf-8?B?NWgyNitvZXJrYll2NUx6dmI1MjJHSjdLWGhBQ3BuTWdINTFKRElGalF0b05O?= =?utf-8?B?TDJseG9RRGpvanptbnZxL3BlWjV5dG55YVE4Sk1yRUJxa1dCZmdYQlovazN0?= =?utf-8?B?bENWeVE2L2tuQ2xCZzRRUW56dytDYy8vQmpOU2tMNStDajFLRStWM2QweVVE?= =?utf-8?B?VFVTdXEyQlhnTTVlcFRnN0ZmN0FWUm5hdENEUFE0WHlJNEVwVnVGT0t6VnRQ?= =?utf-8?B?R25UNTZOQTVMTkZwN0JmYXhEK2p2OGFuNkNDNkFtOXhuT2VYWE43Y1U5Sk42?= =?utf-8?B?MXFVSG04QjF0SUpENitiNDNwWEx5NHZQMnlsVEozazAzV0tLMEJaUWIwSVdU?= =?utf-8?B?ZWZSU2pVcUVZQTBLWFUvUWRBNWNUQkZPc0xKYmtqVnovMUVjLzBLYmI2VE80?= =?utf-8?B?T2pBcGRndS9OVXZOYXRGZU5SdXcvUm9pZEtHWXZDM0NLMHJJM2pIV1p4SnVX?= =?utf-8?B?dWdCT2J2ZnVPcmZWRGd4cFBRVmt2TTN6eTYvMk5MNkw2aGNweGpxV1dTVEVw?= =?utf-8?B?dFljUDJLMVpWcUxES0R4M0R2a2tKQk1DYmljdkRhYmVSZzVDSUtqbU9UTHhk?= =?utf-8?B?dWthd1ZTNE93NkZUek9IaGxHTGs3WnE0VHZ3UEkxNlZvbENiTjM3U3lwQVcv?= =?utf-8?B?M0RqbW5Qalh5VWhla1kyelRvWEd3UUtYY3ExOFVFS1ppVUNKYzhNTjJOeDQv?= =?utf-8?B?V3lqaGpYbU5ac245dldER2R4UGxEamRsYXhyNVdVRy9UQk1WY3NUckFhS2tr?= =?utf-8?B?ejRZaFk0cHdDME9pMFF6RENZUk91MU1VQ0hBT1d0U254TkpaeXovOGhXa1lZ?= =?utf-8?B?SUJ5NFVZdXlZa2UzeERiaTRkNGVYV2o4bDJlaW5hMVpBSUYyeWpEZ1BxbkxP?= =?utf-8?B?WE1NYUtFcVljbnhqVEhrck5Mcy9VdDRJQk50RlBXb2R0S2tJc2R2azNnMGFR?= =?utf-8?Q?h1P/reZEeZ3NuDRI=3D?= X-MS-Exchange-CrossTenant-Network-Message-Id: ef7738e6-33a6-424c-c9e0-08de517b1be9 X-MS-Exchange-CrossTenant-AuthSource: PH7PR11MB6522.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 12 Jan 2026 01:37:12.5616 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: EWFiFmKm90X3zCi/eX6i9yAf0h1WiDI1T80jxUVhSaR82d1BVCcan5aUd2XA7TROY8cUv7lqKQpSHdqJgSKapw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH0PR11MB4999 X-OriginatorOrg: intel.com X-Stat-Signature: ok1rkz7axj7ix79y3b6uf5nsmzfbfa3z X-Rspamd-Queue-Id: 9731718000A X-Rspam-User: X-Rspamd-Server: rspam02 X-HE-Tag: 1768181837-787381 X-HE-Meta: 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 SuSnT75r 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 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: List-Subscribe: List-Unsubscribe: On Sun, Jan 11, 2026 at 07:51:01PM -0500, Zi Yan wrote: > On 11 Jan 2026, at 19:19, Balbir Singh wrote: > > > On 1/12/26 08:35, Matthew Wilcox wrote: > >> On Sun, Jan 11, 2026 at 09:55:40PM +0100, Francois Dugast wrote: > >>> The core MM splits the folio before calling folio_free, restoring the > >>> zone pages associated with the folio to an initialized state (e.g., > >>> non-compound, pgmap valid, etc...). The order argument represents the > >>> folio’s order prior to the split which can be used driver side to know > >>> how many pages are being freed. > >> > >> This really feels like the wrong way to fix this problem. > >> > > Hi Matthew, > > I think the wording is confusing, since the actual issue is that: > > 1. zone_device_page_init() calls prep_compound_page() to form a large folio, > 2. but free_zone_device_folio() never reverse the course, > 3. the undo of prep_compound_page() in free_zone_device_folio() needs to > be done before driver callback ->folio_free(), since once ->folio_free() > is called, the folio can be reallocated immediately, > 4. after the undo of prep_compound_page(), folio_order() can no longer provide > the original order information, thus, folio_free() needs that for proper > device side ref manipulation. > > So this is not used for "split" but undo of prep_compound_page(). It might > look like a split to non core MM people, since it changes a large folio > to a bunch of base pages. BTW, core MM has no compound_page_dctor() but > open codes it in free_pages_prepare() by resetting page flags, page->mapping, > and so on. So it might be why the undo prep_compound_page() is missed > by non core MM people. > Let me try to reword this while avoiding the term “split” and properly explaining the problem. > > > > This stems from a special requirement, freeing is done in two phases > > > > 1. Free the folio -> inform the driver (which implies freeing the backing device memory) > > 2. Return the folio back, split it back to single order folios > > Hi Balbir, > > Please refrain from using "split" here, since it confuses MM people. A folio > is split when it is still in use, but in this case, the folio has been freed > and needs to be restored to "free page" state. > Yeah, “split” is a bad term. We are reinitializing all zone pages in a folio upon free. > > > > The current code does not do 2. 1 followed by 2 does not work for > > Francois since the backing memory can get reused before we reach step 2. > > The proposed patch does 2 followed 1, but doing 2 means we've lost the > > folio order and thus the old order is passed in. Although, I wonder if the > > backing folio's zone_device_data can be used to encode any order information > > about the device side allocation. > > > > @Francois, I hope I did not miss anything in the explanation above. Yes, correct. The pages in the folio must be reinitialized before calling into the driver to free them, because once that happens, the pages can be immediately reallocated. > > > >> I think someone from the graphics side really needs to take the lead on > >> understanding what the MM is doing (both currently and in the future). > >> I'm happy to work with you, but it feels like there's a lot of churn right > >> now because there's a lot of people working on this without understanding > >> the MM side of things (and conversely, I don't think (m)any people on the > >> MM side really understand what graphics cards are trying to accomplish). I can’t disagree with anything you’re saying. The core MM is about as complex as it gets, and my understanding of what’s going on isn’t great—it’s basically just reverse engineering until I reach a point where I can fix a problem, think it’s correct, and hope I don’t get shredded. Graphics/DRM is also quite complex, but that’s where I work... > >> > > > > I suspect you are referring to folio specialization and/or downsizing? > > > >> Who is that going to be? I'm happy to get on the phone with someone. > > > > Happy to work with you, but I am not the authority on graphics, I can speak > > to zone device folios. I suspect we'd need to speak to more than one person. > > Also happy to work with you, but I agree with Zi—graphics isn’t something one company can speak as an authority on, much less one person. Matt > > -- > Best Regards, > Yan, Zi