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 B4F93CF58C1 for ; Wed, 19 Nov 2025 18:04:36 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id ABE036B00BB; Wed, 19 Nov 2025 13:04:35 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A9A5A6B00BC; Wed, 19 Nov 2025 13:04:35 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 95EC66B00BD; Wed, 19 Nov 2025 13:04:35 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id 8044A6B00BB for ; Wed, 19 Nov 2025 13:04:35 -0500 (EST) Received: from smtpin16.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay07.hostedemail.com (Postfix) with ESMTP id CE33B160602 for ; Wed, 19 Nov 2025 18:04:34 +0000 (UTC) X-FDA: 84128131668.16.D938D0B Received: from mx0b-00069f02.pphosted.com (mx0b-00069f02.pphosted.com [205.220.177.32]) by imf08.hostedemail.com (Postfix) with ESMTP id 40D7916000F for ; Wed, 19 Nov 2025 18:04:31 +0000 (UTC) Authentication-Results: imf08.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=BSMyGV8c; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=z0Uoy2FC; spf=pass (imf08.hostedemail.com: domain of lorenzo.stoakes@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=lorenzo.stoakes@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1763575471; 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: in-reply-to:in-reply-to:references:references:dkim-signature; bh=EQBpwQMYE5AtI4VyORZjd6iFzNq5JZWagMwmrAipeZE=; b=PkoBxmOjJlL2htK3Nx38YF+v0RgDitgsfg/gXNcdAE9+cYm8VS8we9/JkwOvzzLeAzdX7U +0MQDc9fgPiLMby0PY08I3Iw4th0dc0guwL0YqiQzLKopjTcAx5jFvUfeB78hdFs7Hz6ch XowQyT2EMGfN4Oxd+Razh3eD0n45EjA= ARC-Authentication-Results: i=2; imf08.hostedemail.com; dkim=pass header.d=oracle.com header.s=corp-2025-04-25 header.b=BSMyGV8c; dkim=pass header.d=oracle.onmicrosoft.com header.s=selector2-oracle-onmicrosoft-com header.b=z0Uoy2FC; spf=pass (imf08.hostedemail.com: domain of lorenzo.stoakes@oracle.com designates 205.220.177.32 as permitted sender) smtp.mailfrom=lorenzo.stoakes@oracle.com; dmarc=pass (policy=reject) header.from=oracle.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1763575471; a=rsa-sha256; cv=pass; b=LRWLGXgsbntd4gx4HNH4eatd3qhNwMucBuxPTJvLcS0imSbWtdudR/PNZlPE6wmj8y6pRu D1C/wbHJYi7OYE1Shdlh4sUl0n8ERDR+TJHyTAwlVLX1QNLb7GHNLf6CeUgmxnRSttP+Bc Di2HiREocUDS5D6+Y/ivBHjaK9+HaKs= Received: from pps.filterd (m0246630.ppops.net [127.0.0.1]) by mx0b-00069f02.pphosted.com (8.18.1.2/8.18.1.2) with ESMTP id 5AJH1Q3j006456; Wed, 19 Nov 2025 18:04:26 GMT DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.com; h=cc :content-type:date:from:in-reply-to:message-id:mime-version :references:subject:to; s=corp-2025-04-25; bh=EQBpwQMYE5AtI4VyOR Zjd6iFzNq5JZWagMwmrAipeZE=; b=BSMyGV8cIhESbCkQ6dWUpjKvOr9vEJ43Iu yWynEVJTxbfBUbD+IXfWf0UTqzT8dlImFhJ4xCp/D8aX4r160E20J/zh+zRp/XAt uo2/S8SQxWsm5P7ScsoMY9nrRbXlUDFoaIWdHY8HR+nVLmT4HaQXsx28jTShGWeB 7FhUJz+lRExB6S3tG2+RTe2qf5e2t2p39rXU0war2hOYAnOK1E0LGWlIRJCJh94R iLN2YIRJj8RJj7m3eVw8XU9JDm1KMt7ZhY+9NnECqPufjdSb/ZxdrDTzyDWVn5V2 65IGI2lv5lHtjpUutGdQeKUa9P7Benpy/pupoZV5rsrnzUaol0rQ== Received: from iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (iadpaimrmta01.appoci.oracle.com [130.35.100.223]) by mx0b-00069f02.pphosted.com (PPS) with ESMTPS id 4aejbbygr9-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 19 Nov 2025 18:04:26 +0000 (GMT) Received: from pps.filterd (iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com [127.0.0.1]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (8.18.1.2/8.18.1.2) with ESMTP id 5AJI1onA035973; Wed, 19 Nov 2025 18:04:25 GMT Received: from dm5pr21cu001.outbound.protection.outlook.com (mail-centralusazon11011013.outbound.protection.outlook.com [52.101.62.13]) by iadpaimrmta01.imrmtpd1.prodappiadaev1.oraclevcn.com (PPS) with ESMTPS id 4aefyn7nbb-1 (version=TLSv1.2 cipher=ECDHE-RSA-AES256-GCM-SHA384 bits=256 verify=OK); Wed, 19 Nov 2025 18:04:25 +0000 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=mGuzJSmLO1cjZnBevJ6ZYCONeI33yJ4o3pogqRxjM0P0l0MY/kIqp048PgoPVSdRkc7u+lE3K8daCiw7GQ2q8qoWwOyrvCUDC51Xzv3atFrjpsYOOuHHz+Q0LN1shvMy1Ob2pVruJvXkN3JUlnQ5Shq2NbEv/Md8AWLF5xMfPF5UVXibA2+ECFPxR3AC2rDOJytWy8mwODu3LYgUEiE/Hj0lOAgqa8Y1A7zBxF1fWOxqOJ8E1co2RgDg9IeWPk1v0PYH32o/Sk/nSCgefnKrFWzYrZBNqHmoX8sS1SZYjwBIbcu8M91Y2d0T6bH/hEHmESlXeEw/Kidn4h7e0vIlEg== 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=EQBpwQMYE5AtI4VyORZjd6iFzNq5JZWagMwmrAipeZE=; b=Ab0C6oygfCHks6mjiheSpQ3tc/xWGgSmIvE6x8M0DNTQMEnEIXfTi+RIdNOrzNLWG64Y4UykPi8rlWXx2LtMQagNbhlP9ViD9p/SdRjYjlBQFKIb435EVwtGz1KxtieXR4HStILvSEAJq5IvtCaxcof1TrbitU2A07G15gckBZwHzgaj1KtJMtBVzMzTzYm8LagXWmKq1aTFZGF6kRzLASy8sg0DNVDJJ84k5I7Pa0fyXNKZxmMvlNzdMvEfNkWx7U9uSvhBzpjaKlpiCj2cSBNBQCsyEVJCrc9mTY/W4LABSoXC27OsCjRYlZm/MQqUKZseIL0GBJbcBTe1K4fhpA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=oracle.com; dmarc=pass action=none header.from=oracle.com; dkim=pass header.d=oracle.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=oracle.onmicrosoft.com; s=selector2-oracle-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=EQBpwQMYE5AtI4VyORZjd6iFzNq5JZWagMwmrAipeZE=; b=z0Uoy2FCDXZ5o7K/hI6CarOy3IIQSMMUlRmiKBVisL7w70VQnpMlJCyKdFHWFZ5wbjKr8n+6ziqyVhUKE2DUF7yMB+A/N5lS4xp67vQjuVjrbqzP75pwcvjLrTj2g/rVLyjLqyeUd1/TKNNSjA2Ar1ViyE5PZYenG7DnysDSqJk= Received: from DM4PR10MB8218.namprd10.prod.outlook.com (2603:10b6:8:1cc::16) by IA1PR10MB6900.namprd10.prod.outlook.com (2603:10b6:208:420::12) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9343.10; Wed, 19 Nov 2025 18:04:22 +0000 Received: from DM4PR10MB8218.namprd10.prod.outlook.com ([fe80::2650:55cf:2816:5f2]) by DM4PR10MB8218.namprd10.prod.outlook.com ([fe80::2650:55cf:2816:5f2%7]) with mapi id 15.20.9343.009; Wed, 19 Nov 2025 18:04:22 +0000 Date: Wed, 19 Nov 2025 18:04:19 +0000 From: Lorenzo Stoakes To: Andrew Morton Cc: David Hildenbrand , "Liam R . Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Michal Hocko , Jann Horn , Pedro Falcato , linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 1/2] mm: propagate VM_SOFTDIRTY on merge Message-ID: <0019e0b8-ee1e-4359-b5ee-94225cbe5588@lucifer.local> References: <955478b5170715c895d1ef3b7f68e0cd77f76868.1763399675.git.lorenzo.stoakes@oracle.com> <20251117145413.badc72b4bbddc0978c64c3eb@linux-foundation.org> Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20251117145413.badc72b4bbddc0978c64c3eb@linux-foundation.org> X-ClientProxiedBy: LO6P123CA0048.GBRP123.PROD.OUTLOOK.COM (2603:10a6:600:310::15) To DM4PR10MB8218.namprd10.prod.outlook.com (2603:10b6:8:1cc::16) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DM4PR10MB8218:EE_|IA1PR10MB6900:EE_ X-MS-Office365-Filtering-Correlation-Id: 87a1e104-d16a-482f-f2c0-08de27961120 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7416014; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?b5pIzEkkfCVbU5rngoW+FtR4H6QKp5kCQ5qnO9JSYhC/sa/OnI50FJhM8wUC?= =?us-ascii?Q?9jVxQCD8/dJrmCMnkKzg56nCrYrQTIaVl6KbLulFgSukgn9JeGTpCMuham9A?= =?us-ascii?Q?0rEEEJwgHlLlsRCMwWuQLovFz42sYEzqm8GG8nSq8836Ixqi4DhMOMBR12eZ?= =?us-ascii?Q?QitMHywG4hTllMEGgx+x9yDOJT/L1c4y9tUcFb+wNKXg4Kqg1kbV3gRt1QWd?= =?us-ascii?Q?HNL+NJWgl/QM2GEHGDq6Mos7+kjk4sM8c/+nox7qLDXJZz3q5pthqkH3/F3w?= =?us-ascii?Q?yEcllnixY/zaKY8hfEuE6Oh7fW2V5pLEaG7tN9UPs4EdMfsdmHyhvl9RnJXW?= =?us-ascii?Q?uDW94rdEkuruSErV8C9JbhhCn6yHi+c+c5cB7jmFY1NKVEe/ip8QyyOtTBjb?= =?us-ascii?Q?2ZKva4H656L+fvKHU6D4kuDHbQIgEa7HzrilH1WPRXNj6hKCwZJrpfR1BWWA?= =?us-ascii?Q?/yT1IhY0/OlAZMvEYxWceQBag8od8lRBXOGgBiVieEi+Yh9ghVvrOIHBTbIL?= =?us-ascii?Q?9fOp8uRWOCW+TO8DMp+gngB61GHJwlXGnj59bYmkQgko4+IGsuts6oh4yHPB?= =?us-ascii?Q?7VAC4fOTcNzC+KZtq8ZkFkOLZKKCb0wnqWNmCkrDqXar7nGOUknlV90fX2sy?= =?us-ascii?Q?pmGhbjCE+4uv8A5NdsCKxRbdu9QbedfGpSpgAyZBwPAkrZxHcI3oTDPnFzGx?= =?us-ascii?Q?ORaMMylwOiFYrmTIdweckKE7Cc6OS25TlUiXppLornECV0afrsKlaniurT/R?= =?us-ascii?Q?axV9YJhlptH97ArCJXZpDI+p6XT2TVNlZnoWlKfiOux0iFNYI+IIo9UD/h9q?= =?us-ascii?Q?CEwPITU2EQdavjeWHIfnp4n4ZGoW8WCtw1+Duh1tPqNIGj6OKww6tkXitOx1?= =?us-ascii?Q?7q7ou+SrQ1h4XdJVvYHzfNqpZye/nuvZPNxIeJicK6TivyCSTEnz16Ea2JmM?= =?us-ascii?Q?OAeqyag9V/QjWYe7BAbSN/MRfcnbJ4hST4lUaegn8+dFywtWzT0wmoZkMc8w?= =?us-ascii?Q?UC4G/uxM2Go+cBqyrcf0w9xptiwOXMIgxlU50FnzP9zAjjI2LwY5EGLoI9WV?= =?us-ascii?Q?OnuMZtTb6w/cqtbvAWB78EcGMOICujYbi2vM+6zztdBDCJ0WgX5Soao5HPkc?= =?us-ascii?Q?QJ/l/iuR7p8X3o12ydZzRigdIGDfylBTwRXA9h/6QW6IKQ6EcZRJlSKznqWL?= =?us-ascii?Q?d1avzyWeq9j3fdhNrK/p+WCKjhotCkn+Gf4NxNnT77RpIqM59KEvr/SRpjb+?= =?us-ascii?Q?nVVxxqB6Coe6hW3f2uykJ43CmlmF1HAFB+YXi61YY3Wg5EdzOxcd9hQV723q?= =?us-ascii?Q?iVgfaZvWZXG68gK5H8VRCJRcvai+gS8+B2H4ubwW3hq0dHNT5QDTpDGMTyj8?= =?us-ascii?Q?qKfJThcAGMszYX5516g9ycvd2tiML/LjXdOCjEfeMppomIxB5LWyOlL8tkTj?= =?us-ascii?Q?rVtoHyOIc+p3kkRpqIqEJIUpbalSEpcu?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM4PR10MB8218.namprd10.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(7416014);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?3j3o7LSP9ruPpSuW48OFoKncO39IDuTH6Wx7pym3/sDJVanto+4MzwuJr7zS?= =?us-ascii?Q?WOESjImHFlRSfAtIU8zkLAsIK6FyyuhDKuTcTcAeuiz/FJaEE4JtUJrZJhlu?= =?us-ascii?Q?UJSFjPvOstwcqoaPCxnSTwIGby9LghQ4nMML10yv5DOlfCw+vxKQDJCDukcO?= =?us-ascii?Q?g/QWMW6xApY2hKXhc3V9AiEwvHXY7HajWN30/R4MpxTQqBqTHkO9qbgw5HJ7?= =?us-ascii?Q?nZJAt8V5KeN90zjXT6Up5sH2N844GqfOMhs7vMl4tSObpRm5mbuRK8tH0giW?= =?us-ascii?Q?+D7llyZSlqEk6oylAbw7cS5oK5MZ/G6m+lgEi4gU4o7sa5sQ5KE3p/r65ri4?= =?us-ascii?Q?eBlzZa4Z+vxMdbTTiqruCnGNllNwFFn5OI4OuIUTK0J3hKRMmUKalaQUPpWc?= =?us-ascii?Q?uzlkCJnMXDiBrQs1W4t/ptEYOW4bnsiMU0h5jHh53CavOkZmbZN+/NRW8+9O?= =?us-ascii?Q?4rJKFxHJ13FjyUWIU/boLoxI0AHDrilUiPAaW0piAUeoHJ6e7nPJgx9eC6Y0?= =?us-ascii?Q?TynjKqz5vXdiBO7DdOQlw32QZlOmcs6A2dgPXpGbl325+wqwbJ8UQR60M2gK?= =?us-ascii?Q?nJH6HB2YKDA4MjC/DNZeqCmGJAJzgs+XvEMuYv8M24uRZXMe1z66gci2DuW/?= =?us-ascii?Q?vErt79LjQxQpoj/6qV6R9R/Brnq3Ot/DHnTG8WouBW8+r6RcTog3IS+alAMi?= =?us-ascii?Q?GSrcDJRn9qq62WW3zTd6uXZAxrNApV72OvUgve3msZCgcKrWDiKK2cXvxlIv?= =?us-ascii?Q?/CrWsNbp1uoexv3fyzFw4swALT9LgPoM90bW5aE8QneIupPG0FNs2+m6bOCs?= =?us-ascii?Q?ObXUR/k81UpcFZetRi8X2VxPwF6qA1BUfkndnXLwg5hslUjcovsrG7CzImAu?= =?us-ascii?Q?dY3qm+273nyvNXXd3hXRF2xH9TgjDjLWxHBqMR/JZlFiaxIdrPSSy0zYZJQ1?= =?us-ascii?Q?wNCHyJoQ7L/ZLDNhZ8rW7Xm+vXN9EgLgczSGbdsKeY75NdXOddFhCUxyMOS3?= =?us-ascii?Q?dY67SaMlbwpfLug4J3VU9mEg1+xmRQCDEu2Hs+BsjYFvp9Qt9invDEY+nhhX?= =?us-ascii?Q?P6Mh7oX/xQRMQSw5k+igdCzf9V/634fI5Sxu8oyCEIPDxTcijgFqitsk+kWI?= =?us-ascii?Q?tb0Rl/kMJq5WO7xm9W9Ft9C701H6mOWPgFnfsH8Gn+BxXy9DUwcXxgMPjHkx?= =?us-ascii?Q?vixGU63AClIN2NALMBqOnywuUFuadRLgY4UKzv5avw0634BJB/7KgrRk2IOj?= =?us-ascii?Q?iehDcXOGvUWetz4yLEnGpUTPtuXQKjFOkCOGdPRAnJCk9ldpyRBDZyKBSV3H?= =?us-ascii?Q?wMXClldVdx17j0UPZHDYeEhzSK8XcWKmf5hgBsMnKfJ9d0XJbHJQzEyIU8Gs?= =?us-ascii?Q?0/vAClCFyAK615llUigRS9rsgBuGat3xV7vZ4/PpNjktVNnAYRcMKtBZf8+v?= =?us-ascii?Q?joTiryrUD4cU3G/qO0txVN861YeS2nUh84+USC1i003gJY+KLXeGFNfA0Cgz?= =?us-ascii?Q?P8f52MTCnLuLRA1R2nwg1sDklLuuoW6w8YxwfJKr4NwtU5Ki+EgsVFNF/9iH?= =?us-ascii?Q?3PXbO4t66SnzUBl4VsrJcpPc67YEfbL61vBxrXAccDJGSL8mvxjBPAfufJN1?= =?us-ascii?Q?3A=3D=3D?= X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-Network-Message-Id: 87a1e104-d16a-482f-f2c0-08de27961120 X-MS-Exchange-CrossTenant-AuthSource: DM4PR10MB8218.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 19 Nov 2025 18:04:22.0676 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: fzAuZwVHJ/WTYNSxxzch9Evjbt4vHAdLjtvdZJQeIEof7DB1X+ypb1HS1hgEqOAtGwA+0+wRazRvY/ggAwyrGgcYSSvzDPuFjUtWkzCQVLM= X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR10MB6900 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.293,Aquarius:18.0.1121,Hydra:6.1.9,FMLib:17.12.100.49 definitions=2025-11-19_05,2025-11-18_02,2025-10-01_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 spamscore=0 bulkscore=0 mlxlogscore=999 phishscore=0 suspectscore=0 mlxscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2510240000 definitions=main-2511190143 X-Proofpoint-GUID: U5RZ3H8v5Bk2zrjvSP5KBVyEJvIR2dBr X-Authority-Analysis: v=2.4 cv=JZyxbEKV c=1 sm=1 tr=0 ts=691e06aa b=1 cx=c_pps a=zPCbziy225d3KhSqZt3L1A==:117 a=zPCbziy225d3KhSqZt3L1A==:17 a=6eWqkTHjU83fiwn7nKZWdM+Sl24=:19 a=z/mQ4Ysz8XfWz/Q5cLBRGdckG28=:19 a=lCpzRmAYbLLaTzLvsPZ7Mbvzbb8=:19 a=xqWC_Br6kY4A:10 a=kj9zAlcOel0A:10 a=6UeiqGixMTsA:10 a=GoEa3M9JfhUA:10 a=VkNPw1HP01LnGYTKEx00:22 a=yPCof4ZbAAAA:8 a=azuKysCBzrfH_OwYvIIA:9 a=CjuIK1q_8ugA:10 cc=ntf awl=host:12098 X-Proofpoint-ORIG-GUID: U5RZ3H8v5Bk2zrjvSP5KBVyEJvIR2dBr X-Proofpoint-Spam-Details-Enc: AW1haW4tMjUxMTE1MDAzMiBTYWx0ZWRfXyHFPrHc+uZB/ csTq3D3abeEujh2udIibCy09zl2Kg9FBVwMrlvznQiEVrt9xE9uazHmQs7Y7xvsIqAvNBp+WqvE k5lQp29g7QKxdPr5xtxOgGlQVPKkLtd2b7/3FGESb+wa6x1e5UL9nFJcD1i3GmcZqdbGMeZFjNg myB228JLYdTXWtXxokWdcvq51hS5YgS9EBy0ugjtmGyBm8qcby40krHnIf/avy+dJ/ZH5D4En7k YMCqcFzH8WTne3WH6j5ERZyQAhWQoRq4ttdCsPIHUx0QDPZxM7kuyIi8tPiHP2SH3IvP5BART7N 4RGXt/eqhzDx8+tNPj52FwJfT5VZhBRy59+fxrqRfmnsZVQFTPwcubQpE0s9PoFTCr+isZ8gg/k s9lyCf1qITqz8SpB5qAZMF8gvIUkQ3dL2+OZ5tzIF9iCOnUvHdQ= X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: 40D7916000F X-Stat-Signature: bf1smoory5jhs1x5nihdhe5yhwxsqrjk X-Rspam-User: X-HE-Tag: 1763575471-12252 X-HE-Meta: U2FsdGVkX18zNEu9HmGdp4N083cmVKUE4XsWtTfSjdNRh6pf4uHatJgHAB367xNvEIPoxflDQx9WPj49Cp0t/HNjqsPhhWocvLbEIMA5uhQ/4PLpkDAMkdIsY9glC1W4Q/gZ4g9wbC6t3CVm6thvn9f8dE6f2SRl4ABcSpPYR8uPdzEognLMLsFBvHZjhdDOHT+mJSO5BPQbDT1n4rp6hC/ATapk3LtySZ6cK45QPV3OIhzhtrxrGYsIrn65oOBRKwe3boAjdRuUh8oxmqsqByBz4hrTOq+dc3fhqxn0/884ixvCNrzaJNubCK7dLKnk7D+kX5k1EAAOKyZyX2HvHxR2zGqXcIxnVOtnEF+x9YjdZejnZ3vDFfSCcOy83peiOkOQHOpd/pk/tEl8mQ3sYZC8d8RBFjC5OeZkwfsJEvA62YAZbJbSdma1ADdcLU0hTpDMEqH48YmtJXHpwCNgaK2t8ym/TlINXeiXbWxS9D30eJVBMfeAnuzHCozTflyvb31y4vz08WuEzdi4a1snlrE8ak9zhIxDfJUAdN2WZUKKI2NmDSB07wraowSUBZPlDqmKlrtx2U9LqAl8Vi/Mx887Tw/l2Qb6o0UHgnDj7ohe+NbKygFTugjXrNay0cs5O9osZ7XSIQypKIM85aCe48HdZLB7fijam3N5kHw2k8lECWF+MsB4SwPyWA16n4/VtCeFzCN2/PoUmBsPegemWEc16voYGCRgS65f3yU+4a5nwkTeg9N4Y/z2b5V2adSKwBF+ibmZL3F6PYbGVP64MiKoG/NDulBWhxtnk0AEpsPsgFQ6kQxUd/C7ZTCQfrYOWA8ETcx7FHDhsDA3mtE1nQmBxdApLPguEqY1z3X1DGplUjt44eQd6y/IB473fvhRw5+cA5Bj9BZa97bw1+vN73zMbSt7eJ6SYBMuACp5LUed6QipyKOk92yqcTh1Au5iXBWie8XrHQMbURhHJE+ ggB9GQot 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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 Mon, Nov 17, 2025 at 02:54:13PM -0800, Andrew Morton wrote: > On Mon, 17 Nov 2025 17:33:38 +0000 Lorenzo Stoakes wrote: > > > Currently we set VM_SOFTDIRTY when a new mapping is set up (whether by > > establishing a new VMA, or via merge) as implemented in __mmap_complete() > > and do_brk_flags(). > > > > However, when performing a merge of existing mappings such as when > > performing mprotect(), we may lose the VM_SOFTDIRTY flag. > > > > This is because currently we simply ignore VM_SOFTDIRTY for the purposes > > of merge, so one VMA may possess the flag and another not, and whichever > > happens to be the target VMA will be the one upon which the merge is > > performed which may or may not have VM_SOFTDIRTY set. > > > > Now we have the concept of 'sticky' VMA flags, let's make VM_SOFTDIRTY one > > which solves this issue. > > > > Additionally update VMA userland tests to propagate changes. > > > > Oh. This patch messes with the comments which > mm-implement-sticky-vma-flags-fix-2.patch just altered. Not sure what > you intend here, so I left it as below - please advise. Ah sorry, missed this! Yes a couple things to fixup below, sorry to be a pain! > > (also, I fixed a typo: s/most/must/, both files) > > --- a/include/linux/mm.h~mm-propagate-vm_softdirty-on-merge > +++ a/include/linux/mm.h > @@ -532,28 +532,28 @@ extern unsigned int kobjsize(const void > * possesses it but the other does not, the merged VMA should nonetheless have > * applied to it: > * > + * VM_SOFTDIRTY - if a VMA is marked soft-dirty, that is has not had its > + * references cleared via /proc/$pid/clear_refs, any merged VMA > + * should be considered soft-dirty also as it operates at a VMA > + * granularity. > + * > * VM_MAYBE_GUARD - If a VMA may have guard regions in place it implies that > * mapped page tables may contain metadata not described by the > * VMA and thus any merged VMA may also contain this metadata, > * and thus we must make this flag sticky. > */ > -#define VM_STICKY VM_MAYBE_GUARD > +#define VM_STICKY (VM_SOFTDIRTY | VM_MAYBE_GUARD) > > /* > * VMA flags we ignore for the purposes of merge, i.e. one VMA possessing one > * of these flags and the other not does not preclude a merge. > * > - * VM_SOFTDIRTY - Should not prevent from VMA merging, if we match the flags but > - * dirty bit -- the caller should mark merged VMA as dirty. If > - * dirty bit won't be excluded from comparison, we increase > - * pressure on the memory system forcing the kernel to generate > - * new VMAs when old one could be extended instead. > - * > - * VM_STICKY - When merging VMAs, VMA flags must match, unless they are > - * 'sticky'. If any sticky flags exist in either VMA, we simply > - * set all of them on the merged VMA. > + * VM_STICKY - If one VMA has flags which must be 'sticky', that is ones > + * which should propagate to all VMAs, but the other does not, > + * the merge should still proceed with the merge logic applying > + * sticky flags to the final VMA. Could we fix this up actually? Sorry to be a pain but better to have the new wording: + * VM_STICKY - When merging VMAs, VMA flags must match, unless they are + * 'sticky'. If any sticky flags exist in either VMA, we simply + * set all of them on the merged VMA. > */ > -#define VM_IGNORE_MERGE (VM_SOFTDIRTY | VM_STICKY) > +#define VM_IGNORE_MERGE VM_STICKY > > /* > * Flags which should result in page tables being copied on fork. These are > --- a/tools/testing/vma/vma_internal.h~mm-propagate-vm_softdirty-on-merge > +++ a/tools/testing/vma/vma_internal.h > @@ -122,28 +122,23 @@ extern unsigned long dac_mmap_min_addr; > * possesses it but the other does not, the merged VMA should nonetheless have > * applied to it: > * > - * VM_MAYBE_GUARD - If a VMA may have guard regions in place it implies that > - * mapped page tables may contain metadata not described by the > - * VMA and thus any merged VMA may also contain this metadata, > - * and thus we must make this flag sticky. > + * VM_SOFTDIRTY - if a VMA is marked soft-dirty, that is has not had its > + * references cleared via /proc/$pid/clear_refs, any merged VMA > + * should be considered soft-dirty also as it operates at a VMA > + * granularity. > */ > -#define VM_STICKY VM_MAYBE_GUARD > +#define VM_STICKY (VM_SOFTDIRTY | VM_MAYBE_GUARD) > > /* > * VMA flags we ignore for the purposes of merge, i.e. one VMA possessing one > * of these flags and the other not does not preclude a merge. > * > - * VM_SOFTDIRTY - Should not prevent from VMA merging, if we match the flags but > - * dirty bit -- the caller should mark merged VMA as dirty. If > - * dirty bit won't be excluded from comparison, we increase > - * pressure on the memory system forcing the kernel to generate > - * new VMAs when old one could be extended instead. > - * > - * VM_STICKY - When merging VMAs, VMA flags must match, unless they are > - * 'sticky'. If any sticky flags exist in either VMA, we simply > - * set all of them on the merged VMA. > + * VM_STICKY - If one VMA has flags which most be 'sticky', that is ones > + * which should propagate to all VMAs, but the other does not, > + * the merge should still proceed with the merge logic applying > + * sticky flags to the final VMA. Also could we do the same here? + * VM_STICKY - When merging VMAs, VMA flags must match, unless they are + * 'sticky'. If any sticky flags exist in either VMA, we simply + * set all of them on the merged VMA. > */ > -#define VM_IGNORE_MERGE (VM_SOFTDIRTY | VM_STICKY) > +#define VM_IGNORE_MERGE VM_STICKY > > /* > * Flags which should result in page tables being copied on fork. These are > _ > Thanks, Lorenzo