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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id AFAF8D3EE75 for ; Thu, 22 Jan 2026 15:47:09 +0000 (UTC) Received: from kara.freedesktop.org (unknown [131.252.210.166]) by gabe.freedesktop.org (Postfix) with ESMTPS id 7D65B10E9E6; Thu, 22 Jan 2026 15:47:08 +0000 (UTC) Authentication-Results: gabe.freedesktop.org; dkim=pass (2048-bit key; unprotected) header.d=Nvidia.com header.i=@Nvidia.com header.b="NeztxjFf"; dkim-atps=neutral Received: from kara.freedesktop.org (localhost [127.0.0.1]) by kara.freedesktop.org (Postfix) with ESMTP id 6B02A404AB; Thu, 22 Jan 2026 15:38:19 +0000 (UTC) ARC-Seal: i=2; cv=pass; a=rsa-sha256; d=lists.freedesktop.org; s=20240201; t=1769096299; b=thY7+qgEhDQXWixVb2EUXvB2fBBcRKY/tltapoUQDu/t2UgtgdZrX+MrTaSs2+cAfzIdb rahDwYWhPN+xUaNp0pHM3s2tliiJXOLWPtU7TzlRX/EqqRMCHX1zRQlzb9n/+HeC4uMA1ES SuyIfAOPZQIIKMfy8fzWEP0thlLzFzb8rlRRzb1md29YyOj5ZPaFS/rjkApd9A3xgEmtfOX B9yAM1lZcn32DKV5fUiFqO/bsY0xGymc2oRpNzlAKudTc2uEIl4GsthE3hi8NePbq95yAOT 9JRM8z66nwTufoBcGpnwGDY8csIrEXxwc5or9jPtJabYX6itOFvDSdwForSg== ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=lists.freedesktop.org; s=20240201; t=1769096299; h=from : sender : reply-to : subject : date : message-id : to : cc : mime-version : content-type : content-transfer-encoding : content-id : content-description : resent-date : resent-from : resent-sender : resent-to : resent-cc : resent-message-id : in-reply-to : references : list-id : list-help : list-unsubscribe : list-subscribe : list-post : list-owner : list-archive; bh=urLRoIBEUIKjiUtuMX6/RhXFrlQUu0ljUyUgyCTDCgI=; b=bLcH/+HZOdPdHioaoRvMOxCU0m8zuDGf5aK5uCMLlRc3njMAFL+awNxsdceeJAmn+mynG 2vjpWjZ1nQa+LfWH2jJEC8SvVK3eSL5CVgIs/JBNNh4VczJG8yeiZXPYoZYIsUKG8Lszd6Z /Bhxmyav6Vt68Ymz8hooQkwta2cJTIUJtbu5KI32k/44hfJ8F9bLDJ/eqA1Xo7U25IoQZpJ v96Dc5stWWyb/EunL/rlVpga01kUpAx8RfZbRcqtIV345zygiiGypgNoUxn7rIIr9XoAqFO KGd2JbQRWe6hQvGs7iaIJISp1Enb+xOqpphBIfjYhtbednMW3BWJTUrWaitA== ARC-Authentication-Results: i=2; mail.freedesktop.org; dkim=pass header.d=Nvidia.com; arc=pass; dmarc=pass (Used From Domain Record) header.from=nvidia.com policy.dmarc=reject Authentication-Results: mail.freedesktop.org; dkim=pass header.d=Nvidia.com; arc=pass; dmarc=pass (Used From Domain Record) header.from=nvidia.com policy.dmarc=reject Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) by kara.freedesktop.org (Postfix) with ESMTPS id DB132403B4 for ; Thu, 22 Jan 2026 15:38:15 +0000 (UTC) Received: from PH7PR06CU001.outbound.protection.outlook.com (mail-westus3azon11010034.outbound.protection.outlook.com [52.101.201.34]) by gabe.freedesktop.org (Postfix) with ESMTPS id 87F6110E0C9; Thu, 22 Jan 2026 15:47:04 +0000 (UTC) ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=Y1hntf+J10Wc+3Hv7poOapR5c8+zLAhhvTiisk8s5Q06AvLBI4+Q+q5xSw0qb+ph5634Y4PP5bnf/ddv6MS+GgxiO5N7/q0wenCky9fmpblNSFiSFaXwARw+f1TKJeKK95u/1qY+UHqiDXt0SHhc3+tnbVSdoUnHYngsULkOUZgLQwYFhUEVRnFo5Gaohf0tOfxh1OCw5zqVvZZQLvLmLLY7ppkcaBgRNImiSj7Dmtdqmk7RXrRcUlEKjEj01LnbHCng0ZMDercma8b3Vda/uJtuSFlBcbXk54D9MCpnObIoEUdQiO9bWI5rhdlIikkTUKPZqh63bSD1sxMRbhOdNA== 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=urLRoIBEUIKjiUtuMX6/RhXFrlQUu0ljUyUgyCTDCgI=; b=zBWm1JAqg/d96H6sksdKd4YBdInKj8eUU6/NSPZ0gtcArmTaDNMpeh7oG8Ue/FcPSJbJo0tOZveibmPfYFlfsIfw5GgJJGPS3WykAVXAZhjer4MppHajUBWf3AfAUJEEBU+90y6LVFYi7HOUmIAFqaqL1Puo8D8I7Vh1leGn1gJ+NTB8cNoGoF6GSi4+5sjlqo8PsU+zT2Tq9pknb5WxbEsyW1CtdZus8fbHLCIePJe+kJxv8f4brkAi9jgaHtavUQ56PUxiEpICihXYX13Wzb94HMBzRl0Lg4QAG7PAxi74fbpoosBduPeQWMceT4dOGWrGtMgltKQYLxVSWTX25w== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=nvidia.com; dmarc=pass action=none header.from=nvidia.com; dkim=pass header.d=nvidia.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=Nvidia.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=urLRoIBEUIKjiUtuMX6/RhXFrlQUu0ljUyUgyCTDCgI=; b=NeztxjFfb/XCKZywgF1ikrJGBwwFfT6XHaov7k8FJ4XH2JOScFhCxjUfVsbdAsXEY1WzQz38Ze9r5020u+EM6FwhDw9Rdcs1S015xHLv4YMgdwdPnj1c9GjTktDPRoIi5oP21+AST9VjoiPoBRvbtCI93yxDur+FNFkveMbVpoxp1FcOGTP3OrOb4Z3zFidocNRyCp8+WOLaOL5EEzDeLywzVMOPW7KkYBdhg2PsP+b5etRuXkvpQBzBgqGkEhvccGtRmGu0QxeDRXKleXIfJ/nXXltmPLi407y9Xba2atb+0Ikj3WQt4XJjXoOo2xlSTIi/5KD7W65sfMhpkf8Dug== Received: from LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) by IA1PR12MB6556.namprd12.prod.outlook.com (2603:10b6:208:3a0::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9499.2; Thu, 22 Jan 2026 15:46:50 +0000 Received: from LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::1b59:c8a2:4c00:8a2c]) by LV8PR12MB9620.namprd12.prod.outlook.com ([fe80::1b59:c8a2:4c00:8a2c%3]) with mapi id 15.20.9542.010; Thu, 22 Jan 2026 15:46:47 +0000 Date: Thu, 22 Jan 2026 11:46:46 -0400 From: Jason Gunthorpe To: Zi Yan Subject: Re: [PATCH v6 1/5] mm/zone_device: Reinitialize large zone device private folios Message-ID: <20260122154646.GQ1134360@nvidia.com> References: <4k72r4n5poss2glrof5fsapczkpcrnpokposeikw5wjvtodbto@wpqsxoxzpvy6> <20260119142019.GG1134360@nvidia.com> <96926697-070C-45DE-AD26-559652625859@nvidia.com> <20260119203551.GQ1134360@nvidia.com> <20260120135340.GA1134360@nvidia.com> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-ClientProxiedBy: BL1PR13CA0363.namprd13.prod.outlook.com (2603:10b6:208:2c0::8) To LV8PR12MB9620.namprd12.prod.outlook.com (2603:10b6:408:2a1::19) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: LV8PR12MB9620:EE_|IA1PR12MB6556:EE_ X-MS-Office365-Filtering-Correlation-Id: 6619fffa-3efd-4f3b-38fc-08de59cd739e X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|366016; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?Ohj6vJhRcoQx0d14rJ+KUVn630uJ0OjyBmRLufFHoNPDUq9wqhGhBsSWCyHs?= =?us-ascii?Q?5YPxYiPGzbTI95G/Tosh/PEWY4YIxyKqM9P0/QFhWN9H+mAkzdX7BMLUzDCH?= =?us-ascii?Q?Wn91BCJnDrMXYm4EUJICmdzS0aQofZS16JC0sAQDjt3qTv2N1wtbBCHiNw8I?= =?us-ascii?Q?vUhWQIIWF8Qiwf13QX48aeQf61Lr0T7AN4a+nofJnV68KFlMU/1H3sp/tVf7?= =?us-ascii?Q?6Uj1NmizFTB6/cO7bWwvKufbN0o64Zi/dul0yyQFl6IZ8hnMBo/nafS5FpZJ?= =?us-ascii?Q?eNzuVqNsk9mIUOLmxZwJICLZBZZ6jmjD3HO2LPkxRt/lsRjmVERA6FLE71FP?= =?us-ascii?Q?WsPStBDbYELQ/N0BdXyKRV29LLI7Ny8/L12N8NJMqUY3gOw6ka3j3UQUgVHF?= =?us-ascii?Q?YHxYfwN8u9zgOznfORp3xh4K/EDQLFIw2qUYuEOwIEdbpNTBkP4xwXw3yzuw?= =?us-ascii?Q?qI0NjfzKRhBQtRStUetRK+QZJjHOgAPtSA6wPc8JH5oEqClCOcstWw4WcWpW?= =?us-ascii?Q?PwmIAogOgXtCUpr2Qp6CP9X0TufJOp+VkIm1uj9PHuFFeU1+0R8Y93g1qIpN?= =?us-ascii?Q?vwbDHpKbKdypgBOD5MHFvFX4JOfc5KHLAVcrcBrIvDi2pOHUNSbPZKKAe0TI?= =?us-ascii?Q?/4h8CXIhFPf7em/wcWgkmMaG0Ig9RlvoIWz1XRm+JfytRqhoiLD4gYIJzXKP?= =?us-ascii?Q?ZsGRoSSt+WAe4lCSy2sbG6rTCZIuIAKRsdDmh5MwHUy5FbQBmJ67RRgAx36+?= =?us-ascii?Q?0j4uuTs7j2ZNJPJbkbDV6b9dFyG4m8Rdm2UL8rbKf+7/wldoB+jStJJ8h9ic?= =?us-ascii?Q?kuIKwaz7Q9ZkUL0ih5rIeFisPLf5vWZ6O7V06+TlbqMD+5oYJZCDxoBf9aam?= =?us-ascii?Q?3FENRWgqoE/vnsMO9aWgfpckUgP3Kar6EDVCY3AjCbFAZVMb2oyqeA9udkyN?= =?us-ascii?Q?m7w2Scy42T4M0KsrKK8Y8XDe5hHecvKaIku5etlKUV4uNiFdw2bULmVVAncB?= =?us-ascii?Q?CPbRGF3S+Cw0jWbeTi3fixQWx559sCNbqikUUBAVmsw8RBKSPI+JVPUV7RwF?= =?us-ascii?Q?pLWJxni5bB3uZGd3a1aiTPnhrFsrKnZvkZoYpNhiJ1NMLBQ85sd67DH53YY5?= =?us-ascii?Q?lB/odiXJhICIDrK0EtAdUy1aCwQsNF8PTI519VIVKDJ+GXZXlDKofSWT0YUd?= =?us-ascii?Q?caerQEosFEqZdm6lJGmJkwPet3yllCN3LyPobXKRrxRpgVq6oc/zkPLu6QCC?= =?us-ascii?Q?vHGm1ZmSd2yUOaN6VIjjcX+l1kzEfSUJCWYH4hue+IhHpbJKQQBMdfEvqtGc?= =?us-ascii?Q?UHlmvKsPF8bHftyzqnCIbTF2UjTAqIoXDw7jEvRWhGFzitJP2y+Tq0v15Gux?= =?us-ascii?Q?YKbjfR6F+ylGNATaeXrun93eJzhM+prGXaa+LX6BxtWaQWgV/K35688NF7l2?= =?us-ascii?Q?gqailK2Dwl6I8WBRCvmNfYjBvQeCAEx0diyWoLUmt8QGMKB7BvxY1CCRSRQX?= =?us-ascii?Q?Ym2O2PVDDKSItKO9pjcjE7WutgsoqKtfGagKU0I/HWLx1s4U0xuQyJmEOue6?= =?us-ascii?Q?ftfkYvUaRqSr/VDgWQA=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:LV8PR12MB9620.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(7416014)(1800799024)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?E5Fs5KJqLjfrfdCxIzohuRce/HV8FgniJIFkYD4lqISS7ma6j3xVErWMm4CA?= =?us-ascii?Q?ssbKy8+xYyEDheYDEu80czgFZxfyxrCGnOe4YLJiVD3saDbtU3wdoZIfzEJK?= =?us-ascii?Q?asGVYAMLbvgvkVHLwvKGAVcTj+RArzJcSO5Yo+jKmBTRpmI0DMWMVH1H6pjk?= =?us-ascii?Q?aQGXK6fP7MLASzuS2r6OQNYaS7UTM8CR/xppROWd5BfDUYoAGBSo928klec7?= =?us-ascii?Q?sg9Z1LsIhaxCAvEGpcvZc6FEjQnMUJpCBTIZ4Gxj1FDNRX/OgHXHGkkgC6Cp?= =?us-ascii?Q?lt22OYx5eidO7HBBhnNhIapEQh0asyouPbFl/sJ1qtyEszYnEKWtSNSukJNW?= =?us-ascii?Q?btraflU4GZHy1R2uf4IQCd/MyMwCy0YTGOGK3UbjK03wAemqq19PiBR33huS?= =?us-ascii?Q?bll0+Sx0umj5xU4zHM5rc5JdMFMsBvEyTkW6TesZNmYiMGwqFr7riOLCOgx1?= =?us-ascii?Q?j5sFdHv291N95kv/WbpI6jooA6wRHJAS36NE15piwyju3PznC4+OSEQ4lTfc?= =?us-ascii?Q?q9PH01RHNZJNHQhbRzeibQPKyAx6Y3FtyT34VGCL9NmIKBBA//AbHVJsES85?= =?us-ascii?Q?fCEhtl3+D6P1kAS7RjSKqu9WRGaCNtmTydxJKeEOUQn+l5vuX7ePYXBhsaEM?= =?us-ascii?Q?1d4dmhNSOyaPSAkwDbhs6m0VA1Ko4UvhrXJ0FhZe5kW2qX0sU/wD5K+mvAeD?= =?us-ascii?Q?kuB7jBYx84y+NQng2Sx6r2qNMDAqPiAyLnKxZGwjySK7ztDNgBIBNOpeicmn?= =?us-ascii?Q?LBPsd2axGHGIVKY1cQpjIcVU5ubYaefwmdu043WIg6ijffnoyM4BTSzlJSzE?= =?us-ascii?Q?XY8OE+gItu8mNXewXzCtjOIP49xs3i62bmGaHRQRxNB0Uq5A+JzKBS1ARlkG?= =?us-ascii?Q?ogGzN13BMsneyWgQWsfEvnXGedVUeG7Q4exZDQcSXAeD7GmG8aXdBKdNj6+U?= =?us-ascii?Q?q+oqISKb0MS9aJSMPE1WzS24VrlXCgqCHV2CptoOYdWQ6/iSon6dAe0fQl69?= =?us-ascii?Q?RG4Bq0wpjUn6hYYwxWE6VnHiBWQEXOoAZZaXRoY9Z6LZMMRhC4hYAjeJ8lr+?= =?us-ascii?Q?ek/Cn18vYZRORri6SiD85LkClJ46PklsEVu3DURgFXwLa2tfHga5C4XUneoV?= =?us-ascii?Q?y1vcsuK0Cg6CMBzsKTwjbHyc5FyXcsW+KgPZjNzTAkHeJEERtvOxvDlXTMv6?= =?us-ascii?Q?gVsR3469y3KZlcLoTM/661eHBBCkLO6n/sHjqLoSSWorSOEgkCMfSapewc6Q?= =?us-ascii?Q?Xnvc7JHSh6hOgM+Sgs9JcIb6XkLx1soLqWQoZa/GI5tgaMQXRYesLe0/hJfq?= =?us-ascii?Q?1aOk43ByRVAGMl1vxoXr2+3FO4h4hDwF43F0gyEj7UiwLoLOe5vZEhEHwlHy?= =?us-ascii?Q?5rLL/6oxihjaRSog6zrqgBgIKXpui9eerb17ERs5CEgYAIblX34y2dZNAnEC?= =?us-ascii?Q?HSL3iFY3eYBZcXjKflIW1BWVpPYpNht1//WJnyaKMDVqYpolMqwNCFM3YOnc?= =?us-ascii?Q?+Ce9SmKXLd8f+VV7WoYMuSCUMHcs8ZS4iZRmtYNLbn0msHoyavh7EzGsgKA0?= =?us-ascii?Q?pqHgZzRRVm/wJUBb1L/wA7vvQBwEWkkzcv8sG9rjxNx25haKT3hnCQgzMrYD?= =?us-ascii?Q?iOH+A5Z98zU3GUJPipZaNiaaxcex0BAvP9+tB1icCV871OqXSjYUvWY1RRtT?= =?us-ascii?Q?x+blK5vG4fjOVBDIvK445VpbdQrH3qG+obXZwRJ1iuQcXOfIlUtTQyTAhN3T?= =?us-ascii?Q?lUMOZfpMqQ=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6619fffa-3efd-4f3b-38fc-08de59cd739e X-MS-Exchange-CrossTenant-AuthSource: LV8PR12MB9620.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 22 Jan 2026 15:46:47.7886 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: 61UuDPbnbQgYaKMW5ue6PUb8TuV9NI6UMg7dVvAEh1C4w7RgdricARs5c63CAC1w X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR12MB6556 Message-ID-Hash: RD4RD5DELXSGZ7VH6CJSHCBKIKZJOBAA X-Message-ID-Hash: RD4RD5DELXSGZ7VH6CJSHCBKIKZJOBAA X-MailFrom: jgg@nvidia.com X-Mailman-Rule-Misses: dmarc-mitigation; no-senders; approved; emergency; loop; banned-address; member-moderation; nonmember-moderation; administrivia; implicit-dest; max-recipients; max-size; news-moderation; no-subject; digests; suspicious-header CC: Matthew Wilcox , Alistair Popple , Matthew Brost , Vlastimil Babka , Francois Dugast , intel-xe@lists.freedesktop.org, dri-devel@lists.freedesktop.org, adhavan Srinivasan , Nicholas Piggin , Michael Ellerman , "Christophe Leroy (CS GROUP)" , Felix Kuehling , Alex Deucher , Christian =?utf-8?B?S8O2bmln?= , Simona Vetter , Maarten Lankhorst , Maxime Ripard , Danilo Krummrich , David Hildenbrand , Oscar Salvador , Andrew Morton , Leon Romanovsky , Lorenzo Stoakes , "Liam R . Howlett" , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , linuxppc-dev@lists.ozlabs.org, kvm@vger.kernel.org, linux-kernel@vger.kernel.org, amd-gfx@lists.freedesktop.org, nouveau@lists.freedesktop.org, linux-mm@kvack.org, linux-cxl@vger.kernel.org X-Mailman-Version: 3.3.8 Precedence: list List-Id: Nouveau development list Archived-At: Archived-At: List-Archive: List-Archive: List-Help: List-Owner: List-Post: List-Subscribe: List-Unsubscribe: On Tue, Jan 20, 2026 at 10:01:18PM -0500, Zi Yan wrote: > On 20 Jan 2026, at 8:53, Jason Gunthorpe wrote: > > > On Mon, Jan 19, 2026 at 09:50:16PM -0500, Zi Yan wrote: > >>>> I suppose we want some prep_single_page(page) and some reorg to share > >>>> code with the other prep function. > >> > >> This is just an unnecessary need due to lack of knowledge of/do not want > >> to investigate core MM page and folio initialization code. > > > > It will be better to keep this related code together, not spread all > > around. > > Or clarify what code is for preparing pages, which would go away at memdesc > time, and what code is for preparing folios, which would stay. That comes back to the question of 'what are the rules for frozen pages' Now that we have frozen pages where the frozen owner can use some of the struct page memory however it likes that memory needs to be reset before the page is thawed and converted back to a folio. memdesc time is only useful for memory that is not writable by frozen owners - basically must be constant forever. > > > >>>> I don't think so. It should do the above job efficiently and iterate > >>>> over the page list exactly once. > >> > >> folio initialization should not iterate over any page list, since folio is > >> supposed to be treated as a whole instead of individual pages. > > > > The tail pages need to have the right data in them or compound_head > > won't work. > > That is done by set_compound_head() in prep_compound_tail(). Inside a page loop :) __SetPageHead(page); for (i = 1; i < nr_pages; i++) prep_compound_tail(page, i); > Yes. One of the issues is that device private code used to only handles > order-0 pages and was converted to use high order folio directly without > using high order page (namely compound page) as an intermediate step. > This two-step-in-one caused confusion. But the key thing to avoid the > confusion is that to form a high order folio, a list of contiguous pages > would become a compound page by calling prep_compound_page(), then > the compound page becomes a folio by calling folio_set_large_rmappable(). That seems logical to me. Jason