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]) by smtp.lore.kernel.org (Postfix) with ESMTP id 32D38C19776 for ; Fri, 28 Feb 2025 14:59:08 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id B657D6B007B; Fri, 28 Feb 2025 09:59:07 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id B14F16B0082; Fri, 28 Feb 2025 09:59:07 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 98F38280001; Fri, 28 Feb 2025 09:59:07 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0012.hostedemail.com [216.40.44.12]) by kanga.kvack.org (Postfix) with ESMTP id 7B4DC6B007B for ; Fri, 28 Feb 2025 09:59:07 -0500 (EST) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 0E98B120CCD for ; Fri, 28 Feb 2025 14:59:07 +0000 (UTC) X-FDA: 83169661134.25.8B71969 Received: from YT3PR01CU008.outbound.protection.outlook.com (mail-canadacentralazon11020077.outbound.protection.outlook.com [52.101.189.77]) by imf09.hostedemail.com (Postfix) with ESMTP id 1026E14000E for ; Fri, 28 Feb 2025 14:59:03 +0000 (UTC) Authentication-Results: imf09.hostedemail.com; dkim=pass header.d=efficios.com header.s=selector1 header.b=kpBwjSFK; dmarc=pass (policy=none) header.from=efficios.com; spf=pass (imf09.hostedemail.com: domain of mathieu.desnoyers@efficios.com designates 52.101.189.77 as permitted sender) smtp.mailfrom=mathieu.desnoyers@efficios.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=1740754744; 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=mTN+oppHzmJ0/2Rx2chpmxRj1ub8M3a6FNkweDIzfko=; b=3wMrThEmMBa8ywL9VCKBtQv7YNtvLBhfDAGLWW0VqZcJem0Ysga2S8WGY8C/7IwuMtmpkW NcXJDIfKfwm1+osabMel4kWVIXz4TMK60UcdV6GjTYI4EHCvbmIGiiA7cDx9IDiQhJWSjf wWSpSiVr0aXK/xoI5QrKtRmruJihHDE= ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1740754744; a=rsa-sha256; cv=pass; b=Zlpoqrwxjr6NxdmBf9nmF+vQgvol0aAWkPCnLNnrnIRu+Gj0eJ3ef93SkfiQJqySu2sK+0 xUxE1SbH3pFHVjJByFvkwuxubsRtH9bViueTAG7kYfEDQDhX3d26PwWJ6TiSuMS8sn0hW0 wUZ9+Pbxk8KEtVMZrROfrNXAl8ggXFE= ARC-Authentication-Results: i=2; imf09.hostedemail.com; dkim=pass header.d=efficios.com header.s=selector1 header.b=kpBwjSFK; dmarc=pass (policy=none) header.from=efficios.com; spf=pass (imf09.hostedemail.com: domain of mathieu.desnoyers@efficios.com designates 52.101.189.77 as permitted sender) smtp.mailfrom=mathieu.desnoyers@efficios.com; arc=pass ("microsoft.com:s=arcselector10001:i=1") ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=yKnF3zOkFjCAUGipahjuKBqj8XP+jzPfRJPUAt79Kh/q8Sw14twUoNBFP/s6PbZ7/6zxH7y96sQIdSsPPLesfjD4PugFl3K7NlwlhSzXkog1olbWRw9VVxOG671m7E3NIDPM49sv0Jv76ACDfQJDvSAeVv5gZOayupLeUkQ5/BVSxXTLBJgKTznB5yR3YJ7hQFLdIWZWKt9Z6LiPrLDF2FNOGAMk1j6kQv0CZdC/aR9meeQYdhLCXs5gm+LqhZsGjQslqbYxvBcJi+J1ccwEXg6yRW32oeDeI8/YqpWb+qXvdfuPOnSTxSe+eDrQENh1NbUEx2eMSTU82ezzt6qVMg== 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=mTN+oppHzmJ0/2Rx2chpmxRj1ub8M3a6FNkweDIzfko=; b=AYJH1TVM3jAe2d8fcf8blidPW/Uu1DoS4zn0PBjVmYSiqYd52mPT8GboULLGLm8vH/2LStgYOuNk7h0FbZmekJGWmRDM2eYJgVMdusWIuNQRktsgdqQkNgNCP2OQLMPWltomCiV8fdnDYyHtxLIrJQBc9C1HH2hN841FdI7cUSfKOw6UAG1Cj6MDClwBsR1KmOfcIz6URdfqHo4rkXXihg7xg4Qafl5St9n7tBX6/ZGsSoHMriKmpxT+LmLgNnfqIpmeYLCPQbPFpz+V52NFKxy+sgaOu+1YQzPXaRwntFVXIZ+Dmb3f8suKPxaAmi0oEhhDh68MJSS3Mzoq44WqMA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=efficios.com; dmarc=pass action=none header.from=efficios.com; dkim=pass header.d=efficios.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=mTN+oppHzmJ0/2Rx2chpmxRj1ub8M3a6FNkweDIzfko=; b=kpBwjSFK9fziWwFD7iEBG30OHn/Qh5AQHMijyYDHTUnDpCJ4xfd6UFw3vRzq1X6GSSISOaDoKDyyfiaCUW+6iaCqbweRP7ZPyXAksITiSN/YFudxEGv1LhIrhwBLE7ebuglOYhOhNVbLgeX0aAYQDiOwMHvY1HDOIK1IxOQENN5Ed5NiPrnCn6ytxGvuc6u/8zcSHuueijpwrBqt5IILraSyFvR3YESV1p6vSxFIzFiy2HeaS2s5Zrn2wHADS8T54ZX6BWOcGrgaR/qadl0igm8RvywIO+VlY/oHsHwxl+/wwDdw3whtGsqcHYDwukEJWsZjcqvbYf3dECH1yXWntA== Received: from YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:be::5) by YT1PR01MB8665.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:c5::15) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8489.23; Fri, 28 Feb 2025 14:59:01 +0000 Received: from YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM ([fe80::50f1:2e3f:a5dd:5b4]) by YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM ([fe80::50f1:2e3f:a5dd:5b4%4]) with mapi id 15.20.8489.021; Fri, 28 Feb 2025 14:59:01 +0000 Message-ID: Date: Fri, 28 Feb 2025 09:59:00 -0500 User-Agent: Mozilla Thunderbird Subject: Re: [RFC PATCH 0/2] SKSM: Synchronous Kernel Samepage Merging To: Linus Torvalds Cc: Andrew Morton , linux-kernel@vger.kernel.org, Matthew Wilcox , Olivier Dion , linux-mm@kvack.org References: <20250228023043.83726-1-mathieu.desnoyers@efficios.com> <8524caa9-e1f6-4411-b86b-d9457ddb8007@efficios.com> Content-Language: en-US From: Mathieu Desnoyers In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: YQBPR0101CA0034.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c00::47) To YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:be::5) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: YT2PR01MB9175:EE_|YT1PR01MB8665:EE_ X-MS-Office365-Filtering-Correlation-Id: 0a27049b-e38f-4653-7d40-08dd58086f7d X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|1800799024|366016|10070799003; X-Microsoft-Antispam-Message-Info: =?utf-8?B?VDREMTJQV2x1ek5pOGJ2TXdvUGhMM3VvMXh1dHJ0RzFBTHhrYlBFUkJrRUxp?= =?utf-8?B?Qld1MDQ5ZjM2Q0VybXEzazJOR2l6eTcrN2NyQjF4WVk3UUYvRG1sdFc5STVR?= =?utf-8?B?N1RkQWJuS1BuREs3eXIzaUJKSFhydzU0dUVHK3RIelVpQ09LZFRlQWxQLzZN?= =?utf-8?B?MDE4Vks5SzhOTktwZC9sYnd2VTNVNXVVcVJ6YkU2Rm1HTStIbXNHY2IrRmdx?= =?utf-8?B?UmxtT1prTVE1eWIwT2Vna0RhR3lXUzd5YjdZY3ZmOVE5TWdqaFdwYkFvSThE?= =?utf-8?B?b0VVMmJuNUdvbTQza2tSTkI2V1lRQXNRUFAxWFZWaEt4TW1xVEFzZUVNSFgz?= =?utf-8?B?TXJaMDBsOXp6ZDk3WC9IOWs0d2dlL3V1N2k0SmhzZnN4ZWVGTWZzMjlTcmlk?= =?utf-8?B?TVBtbFYybTBwSWJ2cVRwTTRUbEl3YXlBb0lmNGpRVjZQVXIxWExWTExNMFlQ?= =?utf-8?B?ZTd4ZWZPZWN2U1hzOXFlb2JwbTdSV2dYdEtUWHVKUmRTVWp1NFJtanZLQXRj?= =?utf-8?B?SjIxdEFTYVEvZU04bTNSSVF3c1REL2hYMG1iOUpWVWNBOEdhT3d2bWJkMldi?= =?utf-8?B?YTNTTjVJL0sxcGtEam9xbm5iOGlDTnNNK3B3dDY3OUh6K0dUZG1kQjloYU01?= =?utf-8?B?OUpDVXlSaUVsOWJvc3grRWFKc3YzWDZVUnJZRGRWeW1OaklTVDRsamNVenpv?= =?utf-8?B?MENtVk1jK0Q2MkRiSk1NNE9PVmc3RHFlMzl0RkdsSzZnc3p0SndKTkNQWUgy?= =?utf-8?B?clVOMEhGVGpqZ3VLWU1xbGkraFFpM0pONWtsNmtOWmFkRG9Fem9keWdPdVFC?= =?utf-8?B?cmdWdmlPaVd0WkFCampSVUdIeGhXMk0wdlBsdFdmbzVnVlBCL3hZU0pmN2RN?= =?utf-8?B?MDl2TVpWVHMxOGVFZmR2RjBGdHh5dVRnZ09OTUY5TjhsNlF0Rk9McTF4Tmpu?= =?utf-8?B?cnVnNUc1ZWNXY0RydG9LYjdBSlliYWVqZThMM2hVNENMODZwOU9zekVUN3RM?= =?utf-8?B?d3RYUzFkaU8wb2IvVnlYSnZPS2Q3Rm0vVU5SMVNQeXkzSXVoK1VPNmlXbzhL?= =?utf-8?B?Nk1jeEFrV2QxVW5UZmhxN0FGME1IWGhkVWk2Vy9BZUovS3E2VXhuUTlGWHFT?= =?utf-8?B?SUFKYjdjckc3Q1hCWHB6bW9KbkE1VkVKd1g0YWN2elV2K25wWnJuL2h5RW1B?= =?utf-8?B?RUFxMDBiS1BtVW5LUTkzWHVBdjI3ZmVweXJWb2ZPZStEUjZrV0JhN09uNy94?= =?utf-8?B?MDdGY2JPNGVRZzVqVytyUU0rS2V2c0p6U3B0VjFnMzJWOHpTUzY1V2dOTGFF?= =?utf-8?B?WEdmWjBzeFY3eFVSUW1NNVJOTVNwSXBNTlcyQzExOC9uMTdEdVEzeDByR1l6?= =?utf-8?B?dVloTDlwNTdOenU1SFl5NnBFN0U4NXlNeTZZUHh6QVdETXdiUnRuQ3R4ME9j?= =?utf-8?B?ZlIySjFzZm0yNzhKZzR6MHBWRlV5c3QwK0pkYUJHVFBGVWdzOGNYVzlEOHFk?= =?utf-8?B?SzJsMjRoNytuOUhtSEI0ZDhRQWxZZnhSNHdMRmdPbTc2bjd4ZmhsV1NXY09Y?= =?utf-8?B?aWI0ckJHUjVweldEeCswSUs4RC9xM21iVHhPZ05HUU9yRkNlUDVkemRtejM4?= =?utf-8?B?ZXliYnU1aUFkdEVudHVocVlQeStWTU5KTnR5Skt4azRYeG9CbWRFajYyR2FX?= =?utf-8?B?dGNnOTJoZ0ZlSzUxbEdEeDNhWndwMmxJVTJlZUhNdUNET2ZQTWpHVHUvWExI?= =?utf-8?Q?OuefYNoGiflDGRbRu2SSWtTeJZtlghGV+nAS0vu?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM;PTR:;CAT:NONE;SFS:(13230040)(376014)(1800799024)(366016)(10070799003);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?c0M2WEFGRVhtckV0RmxYNHR2QXVlUUZ4bDFORTB4S1lvTmZ3N1p6eXJ1UWdk?= =?utf-8?B?S3BTWERVelNDRmFZTSt3TFdPRzFJZDdJQnRmVkVGbEZIanQwNmZLdzFGQno1?= =?utf-8?B?SHd2NW1yTVB1TnFWYWZ3TEJyUDNKUlRZbDdTOFh0VFl2UGE5KzhoYkRlbnhC?= =?utf-8?B?bjMrL3pYYjZNOTE3SnRWeXB1d2d5MExMLzBZTDZRWTJUSFBtS3JrZnVSVFZJ?= =?utf-8?B?VFlZQURSaUE0bDFrS2JWS21NUTdVQWxUVzlNZFIvUUhUQXBiT2ZSYkliZ1Zq?= =?utf-8?B?RFl0WjN2bURubjQrRXJSQ3Urd3BmaVpKQ3Z0d3BNYkg4YTN3ajVldnhyT1BX?= =?utf-8?B?RE51a3p2NDZXTTVBL01LVWQ3ZEpvS1pLOWtmdmc2QzkzWGtDYnpaN1RBVXQ4?= =?utf-8?B?STJDT1gwRlNWMUNUandXUmFyY09UNHQvOFBhQnpFa2tia2xJOTh5UnZONkZp?= =?utf-8?B?eTZMaU83N0ZWSnVLbTVROXE5dWZORE43dGQ1WHdQUmVDL1FBVzFDSmZJbWx0?= =?utf-8?B?NDF3Rng4b3phWlBCWW51eUZtT3hqc1RZOUhJcEIraWNEWU1TS0w1MUZaQTBh?= =?utf-8?B?SGpUbXN4TGVnTnNnV21jdDNJUGJCZmJLQnVEamNkT0RMdmpLYmpsejN1RTlx?= =?utf-8?B?dFZJWDlQUHF5SHI3c0dBcnhKSDlHK0l1UUhjajBaejVyRGZQclJnOXNFVFkv?= =?utf-8?B?UGEyUm00WEY1eXNRZTJyektsUkhIMlNUaEp6alhNWWVxY0oxTGJVbGF0ZXRt?= =?utf-8?B?VVhqeEhETmlYYVp0VzBCOTEzTmNNajd0WGN2MnZMS2g2aFQwRklNTmgxSGMv?= =?utf-8?B?WG91ZWNMQTZPdUtQQktmTHBGM0VhMENseENjd0JROUNxcUlBOVcxYkRNd2JK?= =?utf-8?B?L1B1a2JwemoyRGZGT1lZbm8yWHhBOTh2NThjSTMxOUE5dUowM2FENTUrVmtJ?= =?utf-8?B?R0h3SDMyNmEvdWZWWkswaWw1VnhZb01xZUQxZWdBWU1waFVtV1RIUExQVzdr?= =?utf-8?B?SjRWbGE0K284aUx0SmJiMmdWcndkaXFZT1ozdTdKdS9KMlQxTUQvbU5HMy96?= =?utf-8?B?NHQ1Y09Gdysrd0lNMXU1eEdWUlFrSldLcWdRMyswREtQUVVxd2Y2NGsrUEZh?= =?utf-8?B?OWRhR0V2bzJQOEh3bFJ1MklNT1poMkdqSXk0OXBUYzdpd3hQR2N3NzAvUXh0?= =?utf-8?B?Y0svak5yYkJpVmxPQWpzWkVHaGlyOXllc0VVWURHR1UxRWhhTzRXN1NvdmZa?= =?utf-8?B?WTB0dHRCRXVvaEFudmlZeTFoNDRQaWJvUml6UjBXcDlQQkpzM3V1VWFJYkpP?= =?utf-8?B?d3dxNTBmM2xyV09iQ1VSb2hrMmNyNytURzRLSzhkNEQ1Vyt4YlA0SHZXYzFp?= =?utf-8?B?dWpzTXQvUFRFc3pGS2xVS2FNZktvL2EvVm9PL29RcWRrallPaVg2VERzZW5R?= =?utf-8?B?c0tTemZnNCtkUVpMcEoxYTBWOGluL2JtSVpNcUJBS3J5MnoxQlpjS0NIaDZt?= =?utf-8?B?MnNMTU12MmFac3d5TCsyM010b3F6Q3lPd3lJemlJRlBBcDVaWW5EVWhqV1pk?= =?utf-8?B?V2QzRmRBYkJldUhsUGFLYXY5bnlmQXN3aXE1VEZmc1VrbW9JQzVBMkxXU2lR?= =?utf-8?B?ZW9UYURUTWgvT1NHQm5na1RidkhwNldHTmlCN0Z2enJod1psUmY1MnZLYWt1?= =?utf-8?B?V0p2Y09VNk5QcHdOTGExK1VIaU1jQ1J6Y3RwQkVXbUQwcnpXVDBlQmgxS0NW?= =?utf-8?B?SzVQU1BjMnNpZ2tUekFSckVadm5xMi8rbktvamVQVWZkSktyU1VVZFVvY2dS?= =?utf-8?B?QlpHOURHakt0MU9tWkxhK2pPOUJ4T2F5Vk1xREFxeVZxZ2E3L09UbDN3ZGkw?= =?utf-8?B?NUZiRHMxYzdLc083d2tWRXg5OHZZNDdieWVGRitVREZQeVlpUExpSm5YM25w?= =?utf-8?B?Y1dSTjVvTUNBTmFZd0p2eVl4L090K0dYOVdSWG1OYmRMMjM5K25DejhHQzBN?= =?utf-8?B?SXVjekgwTzJLOXpnUFhTbVlhKzRnZUFWMmIybmRuRTVDRmt6eHdXWXgrZ2lI?= =?utf-8?B?Zk9Ra1QxN2lYK2g4aWQzRXdOdTFTVFpKSGhNRmR0bHVLSWNNazMzRUhLMm5X?= =?utf-8?B?bVNkaXNWYmtYUkVTV05Ecm9hM3FrV0ozbmVWd0oxSEdrOFpCT3VGeHl0eXFD?= =?utf-8?B?NkU5V25oUXk2VDlSdTZCbFBSTmxUVWY1SWRxRnVKSzhsdUlqUUUxT3owRnky?= =?utf-8?Q?H6wG0ElBdKs/7w3r0E2anpsFTaQVhKsbPw5LxJaAbU=3D?= X-OriginatorOrg: efficios.com X-MS-Exchange-CrossTenant-Network-Message-Id: 0a27049b-e38f-4653-7d40-08dd58086f7d X-MS-Exchange-CrossTenant-AuthSource: YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 28 Feb 2025 14:59:01.1375 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4f278736-4ab6-415c-957e-1f55336bd31e X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: iKphgFEiVtDW/lf0dU93+Bp4wi0WjgWypWr2zsObFHH8IZYB5ESpEoEqMnQe5mxI9QDoVmk66+ufjjH+V9VrCKv0g/7DAVNtCeZ29KJOlpU= X-MS-Exchange-Transport-CrossTenantHeadersStamped: YT1PR01MB8665 X-Rspam-User: X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 1026E14000E X-Stat-Signature: xdgc93fxxdjmihyzhujwch3g8158dng9 X-HE-Tag: 1740754743-938922 X-HE-Meta: U2FsdGVkX1/ETcxOgiJRPzJLj47Moi8iQIFZFs1j4hJ9nJWIlY/wR+Q1oRcQoBJYPlTPuqjpwnev5rxmNJcfIc8FMObxJWIU/lpWXjtnXAGbKv0+RBYlr582fRBtAwtPw09XxM5AV+dLhu5SS4Nn3mx1cZBb/XO8VLHYCrDBM9mvWYEJTy6MyL3Bb+/ZaalxOyThm1pzbTTdqe7Exb7Q8jyjq6maK/fkkJKGdtoZo7cDDAXQCmE9fuasQ2oJEjhjfcEzEdr+lSne69F3kZjAfT4WwhxTYX92W6BAEhXTakYtVkPiW4pGmFaBsdcJTZTQQ+vcoWHnP30UlHzgRZo90F9/4PTt3OuBwuqRGAXsfVO/73d8IBbVgLilsiz2ZVIwHT0TbV4AOwzT7mmoyl4KuYGq2B8VhRBY5P1jBxO2lHmPhc5DZWLoX3fY33pCZOO06qRAYhjg1H6nZ+JgixJvM3/oyhVmYy8RnU5sQdfdiI4D5S2wulfW/0kEk4sN6Ir6G0ZTOo53+gD1QCmwLDX1HIoNMXkuz8hzGO4cPvLJBg5IQPtJPmYbvChd9frAFDGS9l6de4cwMfS+AYd5t4i198hoR9im5VVwZeBr3Rua1nJupLxH3f5Hh5y/rjgpQ+16mWFJm1D13S7ZKbS/s/bc3jNPu7P7z3Kr3AOzZPmhhWVWKMB47Uu4r8bhJlEnpgQF/40sJy6ePjpf4Z19cuvXzU4+ZEYVYqcBxx9yyaWpzPur7XOH/HfIPYl4tojgHPq96PDWU/I06ccbouJJHsBGdElu7xOF+SwFWxe8GtSKJ+YoPkWAzjsOatBVyn/gOv9TV/xBt/VazBf+Vcmu/khGb+0vfIERQ/pmnSP0Xj1uqKNhw3MibBeHjcYFJ4v9VQux/A9Ck/1jVKfxej/uSsjiUTs+AwYcuIryfq93BNtrwYF009qz3Bmi4NeScKjAygQBrF60mHJZYVVgtYxVFRi VahdeyxM mwX/N1vLonzrCZML4tXh4QoGY0elVlfRnnJ1JYQHSzdz3zw8/GDT6b4IC2qcUm+K8BckfTkNUTla4z8ZT0I9rc8H8k4a/Mi4luJuTL8/K5MUzdblyRanDpj8ZNOUxXxCiT9DGGv+5PtCxQ0Y8yZCdpzJ/kDTiCwnbATbEwS2clF70+1UvgSNvDBgbBYLh3LU+MUKgb7YV3uIOy9rnSxThzSMeBJZ1X3OwTdktukzDTB6PbvChtTke00T1yau15sgc9zq7PmuzRv9BJDsXjPWB1DDXar36VVYcr5B/s5tUZ0C9RlLNcIyDLgfikCz3OTQLsqmd4dvM54MVZnX7mmB73RPMSdME0bFZJcwh4nLjcf5wzk0ScZqFZIEDLQ0SKtVw8C2afP8Vu1v/ZoZ9Fm7Qe3MyO3K9aqs3nFLGuc1D7pRU4OFdXUbtA1908YLtdKNxNlylwsnrt1Ohktybn0Mxlq9CDutqbT3FxtKc 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 2025-02-28 00:17, Linus Torvalds wrote: > On Thu, 27 Feb 2025 at 19:03, Mathieu Desnoyers > wrote: >> >> I'd be fine with SKSM replacing KSM entirely. However, I don't >> think we should try to re-implement the existing KSM userspace ABIs >> over SKSM. > > No, absolutely. The only point (for me) for your new synchronous one > would be if it replaced the kernel thread async scanning, which would > make the old user space interface basically pointless. > > But I don't actually know who uses KSM right now. My reaction really > comes from a "it's not nice code in the kernel", not from any actual > knowledge of the users. > > Maybe it works really well in some cloud VM environment, and we're > stuck with it forever. > For the VM use-case, I wonder if we could just add a userfaultfd "COW" event that would notify userspace when a COW happens ? This would allow userspace to replace ksmd by tracking the age of those anonymous pages, and issue madvise MADV_MERGE on them to write-protect+merge them when it is deemed useful. With both a new userfaultfd COW event and madvise MADV_MERGE, is there anything else that is fundamentally missing to move all the scanning complexity of KSM to userspace for the VM deduplication use-case ? Thanks, Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com