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 40085C54EBE for ; Tue, 3 Jan 2023 03:33:27 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 85C7F8E0002; Mon, 2 Jan 2023 22:33:26 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 7E5D38E0001; Mon, 2 Jan 2023 22:33:26 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 5EA018E0002; Mon, 2 Jan 2023 22:33:26 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0010.hostedemail.com [216.40.44.10]) by kanga.kvack.org (Postfix) with ESMTP id 4809C8E0001 for ; Mon, 2 Jan 2023 22:33:26 -0500 (EST) Received: from smtpin02.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay03.hostedemail.com (Postfix) with ESMTP id E2D0CA0632 for ; Tue, 3 Jan 2023 03:33:25 +0000 (UTC) X-FDA: 80312067570.02.A4969C5 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf02.hostedemail.com (Postfix) with ESMTP id DC9C880012 for ; Tue, 3 Jan 2023 03:33:21 +0000 (UTC) Authentication-Results: imf02.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=hyKjKSsC; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=pass (imf02.hostedemail.com: domain of wei.w.wang@intel.com designates 192.55.52.88 as permitted sender) smtp.mailfrom=wei.w.wang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Message-Signature: i=2; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1672716802; 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=LatRCUBthXhJ+o+53LiWlHn6mK7KBbJO6MDf7+3N06c=; b=TvRax3GMPKlsM98aNL2GJviC2tJXYwzNfP/KLu6r+p7wxmdRbIyG0mzjgJX3t15bJPSD4R lgJJMGLcyA4tDsmdjnjlBiCNP7L53mAhtxNIRA7RasKxOTia641TPOHkazqfBgRkJaRTs0 0WGhUIa3/IBn3Xxdu5QIA9A4hR6bIsA= ARC-Authentication-Results: i=2; imf02.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=hyKjKSsC; arc=pass ("microsoft.com:s=arcselector9901:i=1"); spf=pass (imf02.hostedemail.com: domain of wei.w.wang@intel.com designates 192.55.52.88 as permitted sender) smtp.mailfrom=wei.w.wang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1672716802; a=rsa-sha256; cv=pass; b=XOjBkniprWV66k8cVMZlFRkAJvMwG4dkv74yNgKncokZVAC8o61Xf4Z+OVKTXZl4mQMPfX SUBCQkXv8WlkZ9t8rQa5sB2qWZ2iGVSC+S5VrlDEpgdOH0ec/ShITfMiq9t1A8V/MAG8ka /zGXNnO95OXeFJLbK+KwOSBRrFxMVzU= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1672716802; x=1704252802; h=from:to:cc:subject:date:message-id:references: in-reply-to:content-transfer-encoding:mime-version; bh=LatRCUBthXhJ+o+53LiWlHn6mK7KBbJO6MDf7+3N06c=; b=hyKjKSsClcb/mqWO3WxSxFvTZDrV1YoXCwKpDuId/9InUY/tBENyV3P9 zTfQs4i7sv1PcAEfLJ/jB6PhVLwIAbgG72YY0FeGECDye1yksim/0hIVh KBr5nwI3WnOqq6soX2BV2HiYtNnu4qNARPFXIII24+xCG2CaID77W5cw2 wymGrdtm1W1aN++0NzEXFzOHdVk2VkEpZ9lByG6CZviF1F5NeGgqxtP2s XP43xOfIwYJaaFpHijmHLGzbm4Tbau5u6HjK0bZterSlpm/1jpJbX6HwA jyjgFI5mNwnZ2GfdRNGPJWm4NZgF7Xah78lRzc1YW38ag1x8mHjXAlGOK w==; X-IronPort-AV: E=McAfee;i="6500,9779,10578"; a="348796292" X-IronPort-AV: E=Sophos;i="5.96,295,1665471600"; d="scan'208";a="348796292" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 02 Jan 2023 19:33:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=McAfee;i="6500,9779,10578"; a="828721606" X-IronPort-AV: E=Sophos;i="5.96,295,1665471600"; d="scan'208";a="828721606" Received: from fmsmsx601.amr.corp.intel.com ([10.18.126.81]) by orsmga005.jf.intel.com with ESMTP; 02 Jan 2023 19:33:18 -0800 Received: from fmsmsx611.amr.corp.intel.com (10.18.126.91) by fmsmsx601.amr.corp.intel.com (10.18.126.81) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16; Mon, 2 Jan 2023 19:33:18 -0800 Received: from fmsedg602.ED.cps.intel.com (10.1.192.136) by fmsmsx611.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.16 via Frontend Transport; Mon, 2 Jan 2023 19:33:18 -0800 Received: from NAM10-BN7-obe.outbound.protection.outlook.com (104.47.70.100) by edgegateway.intel.com (192.55.55.71) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.16; Mon, 2 Jan 2023 19:33:09 -0800 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=IdwrJpqXuM6rbJ8mitVGy2jz8J5n2BTDpHh1nUFB7kAqi2p93D12NLG4TzDky8txew+IziroGlc2A4LCAwasGGxU/DAhOMrTUfdLljm3TnRWa9/sFf2TIfchN3FVLwqUmXj9TKcBQXSOJJT/b69lZ2gUuiw5ivX0CEvxWomCQQwANiQt6FKLgAUsFayj8dcB27tHlNlDy7O3DFQWDBpkRjK3tThBvCmkhqVxLuCAQmqEfbyR5jDszKJ30WT/9NsMxWHNRUyFcNvSoUS7/SrbIzvNUMljOl8fHLN2sfydTIlpGJ0y418pKRGtCImJQGrP7nSVUbW3Bb9W6Q74USh5cQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; 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=LatRCUBthXhJ+o+53LiWlHn6mK7KBbJO6MDf7+3N06c=; b=Cng5JrNyeBMvDOYo5ETM+EzPIjX+Km9o2fThzaRMPEk1wy2LKWxA9LshxUMGujDSOQfHs0vHew0+tYnD6MVlzrfOD272JN9ZMaC8rDm9CyfFnnvhfEx5w4o1+Ro+WRjYBPdZFRSPe3CHXJWsE0H2P9hx91EDFHSRF0iT5d5rmUNkhJChIVkGiVSOBcdL3yxRUj+PEGAkQndhShFZxmhljzliVbUqb+Eik7KL8E+g7KLnKBj7/VN07/RjLjD90SnuTsPXnbi76qRvkTVkXmL2Xgoo80cCr5QoFKSzuFaqVRvEJoJVnWG3eqQqKsdzRQHJ+JSwuoisO3KmVW7ECIjTZg== 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 DS0PR11MB6373.namprd11.prod.outlook.com (2603:10b6:8:cb::20) by IA1PR11MB6420.namprd11.prod.outlook.com (2603:10b6:208:3a8::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5944.19; Tue, 3 Jan 2023 03:32:53 +0000 Received: from DS0PR11MB6373.namprd11.prod.outlook.com ([fe80::97ed:f538:dc6a:a9c4]) by DS0PR11MB6373.namprd11.prod.outlook.com ([fe80::97ed:f538:dc6a:a9c4%6]) with mapi id 15.20.5944.019; Tue, 3 Jan 2023 03:32:53 +0000 From: "Wang, Wei W" To: Chao Peng , "Qiang, Chenyi" CC: "kvm@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "linux-mm@kvack.org" , "linux-fsdevel@vger.kernel.org" , "linux-arch@vger.kernel.org" , "linux-api@vger.kernel.org" , "linux-doc@vger.kernel.org" , "qemu-devel@nongnu.org" , Paolo Bonzini , Jonathan Corbet , "Christopherson,, Sean" , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Joerg Roedel , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Arnd Bergmann , Naoya Horiguchi , Miaohe Lin , "x86@kernel.org" , "H . Peter Anvin" , "Hugh Dickins" , Jeff Layton , "J . Bruce Fields" , Andrew Morton , Shuah Khan , Mike Rapoport , Steven Price , "Maciej S . Szmigiero" , Vlastimil Babka , Vishal Annapurve , Yu Zhang , "Kirill A . Shutemov" , "Lutomirski, Andy" , "Nakajima, Jun" , "Hansen, Dave" , "ak@linux.intel.com" , "david@redhat.com" , "aarcange@redhat.com" , "ddutile@redhat.com" , "dhildenb@redhat.com" , Quentin Perret , "tabba@google.com" , Michael Roth , "Hocko, Michal" Subject: RE: [PATCH v10 2/9] KVM: Introduce per-page memory attributes Thread-Topic: [PATCH v10 2/9] KVM: Introduce per-page memory attributes Thread-Index: AQHZBhXu7Ax4+tqGyUuhRxsCPgD73q6DIGyAgAj77wCAAAbkkA== Date: Tue, 3 Jan 2023 03:32:53 +0000 Message-ID: References: <20221202061347.1070246-1-chao.p.peng@linux.intel.com> <20221202061347.1070246-3-chao.p.peng@linux.intel.com> <1c9bbaa5-eea3-351e-d6a0-cfbc32115c82@intel.com> <20230103013948.GA2178318@chaop.bj.intel.com> In-Reply-To: <20230103013948.GA2178318@chaop.bj.intel.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-ms-publictraffictype: Email x-ms-traffictypediagnostic: DS0PR11MB6373:EE_|IA1PR11MB6420:EE_ x-ms-office365-filtering-correlation-id: 9892dbcc-5ac8-41c4-27df-08daed3b326d x-ld-processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr x-ms-exchange-senderadcheck: 1 x-ms-exchange-antispam-relay: 0 x-microsoft-antispam: BCL:0; x-microsoft-antispam-message-info: 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 x-forefront-antispam-report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS0PR11MB6373.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(39860400002)(136003)(396003)(346002)(376002)(366004)(451199015)(55016003)(33656002)(64756008)(8676002)(66476007)(41300700001)(66946007)(4326008)(66446008)(66556008)(7406005)(7416002)(52536014)(76116006)(5660300002)(8936002)(478600001)(26005)(71200400001)(53546011)(186003)(6506007)(7696005)(110136005)(316002)(9686003)(6636002)(38070700005)(54906003)(86362001)(82960400001)(2906002)(122000001)(38100700002)(22166006);DIR:OUT;SFP:1102; x-ms-exchange-antispam-messagedata-chunkcount: 1 x-ms-exchange-antispam-messagedata-0: =?us-ascii?Q?0euRj0C0gwYDf1F/xYNYAMOR5qffSfECF+y/peU6UVAfIobbvlRj4BGHCUte?= =?us-ascii?Q?r5ZXwa/tC1R0p4/G1NuUSSMuptirSyY1fGke2752HxpH9b25br/rcRVoDfEB?= =?us-ascii?Q?vc/pPiYN3IUpK0ttH2IIiIgPnMaLfTY80+kZgF3pC9h34BjPiAy7fKTujbdd?= =?us-ascii?Q?qxi7F/SVJWOysan9dnug52oH8kE5i6+Nlw+FZwKumu+dh3240nNJuRxPXrZ8?= =?us-ascii?Q?8+r3hMEYj4sxIH3/LldX8bwjScUKq1cC761ij4KmZmjqCO4YqCQk/CR/yYHF?= =?us-ascii?Q?IMF0N2slwWbI6ZyLCr5FhIiq4wepz4iVCygpJbf1s8U/jeBSAHk7GHEjQzFU?= =?us-ascii?Q?nlV4mon0cCeryiTOt/InJDnIL9SJ+6MXKtSTnBiDzT1J5voQYP/6akDt1PSL?= =?us-ascii?Q?BKjgQf3udwM+LOxKngrJpB1PN9YzdndFa6eNk7QIECywDICtYAWZxeucwEYi?= =?us-ascii?Q?nFeqOLwv/yspqJfOAQl9Jegd8A+DFW3EXM9dFDDvD2KfTFr85zw1dd5c0P8A?= =?us-ascii?Q?sR8HI9ZglttSEJ4ogQSZDfojtcs8ABKCErcO/H9DAamLgSM7rz8l40WMzOOH?= =?us-ascii?Q?0F8D7OHhG53fnLf0TL2ATO/z/Zz5JyZMUktYsjPzxcD0HKADaEwZbtwJBQYJ?= =?us-ascii?Q?bdsJi7zKtILd2+MWyVp6HgohTX9MbPE26L3ej2jbuAWz4v8psQbqMuxF0OhX?= =?us-ascii?Q?YvwYrvav1jIPYHHuI60A75Yp4BuSYCOf7RHE2bsalalUTzqqo4OvGX2gsCDe?= =?us-ascii?Q?jL//+JMZ8mucpJBramwGvywvuI33z21Qhgi1ZhyG98IGmald+DJrInOwZkTz?= =?us-ascii?Q?+bj6ynmbDGdk4qOACOB+p0hxm9KYDRg+M4HkRhzwIUxPn9/O8aiXPSqHNqUi?= =?us-ascii?Q?4sDTrRNOqyOAJi/Vf6+SL21jj+Lw0rA+evz0MJ5+3j/vzsATj4YphfTQq1ft?= =?us-ascii?Q?EkmaLBIgxRF9RZCIXGdaCikUYmyl/by1W+gnNFnVWpcJmSR1kTGCemO1hM+R?= =?us-ascii?Q?zriZ/L0GTDnyiMU3fes6QSv8z4gTZb/gWG9M4S6PxcnBiqGF1I2pGhrpT1g5?= =?us-ascii?Q?0ma5cyOBC0UzN4bz5fh/GlLgrogA3Y8yWBSKe71dRud+nuxz3GUcfUFLWMCV?= =?us-ascii?Q?1qT71KhgvikU699+5HoqxWjs6ReWAaX0dwyj4Q+DgCn2UETwb2mQg+RcD1wb?= =?us-ascii?Q?FREJwcBr5mujLyxfhBJpSK6uIcqGUmrFbdBGPVshq6G+ujyF9ig6epXs+10M?= =?us-ascii?Q?2Bx5VsMvB7Jrbj4H4REngPguRv8nI9hAAZTiAADzvxSkxwx6lAmXz6WdD2Sm?= =?us-ascii?Q?Lbe4aSRJiaMOtrHZDfUoJ3OEAJev2dIueoe7fhM5s6UUkE9zgWPYBmjsxzR8?= =?us-ascii?Q?s58lDn+13A1HvXKNXb0wUrxlWIAQOgRpPtQ7dlsxGAxTH3R5ipar/Iln/oNG?= =?us-ascii?Q?9xpgQYUPWKf0HOxkAKtjIXrUXIRhqX0t5PViURjQAHwnuUGaVRjpEQWXFgly?= =?us-ascii?Q?78D+A7n+dODdzed4Qm24gxnVoT/gAxS/EWwgcShLNw5W27kjJlNs+zZl4ler?= =?us-ascii?Q?NFJYDazcX68InRNxlmpHNdNkBh/vfWRMOiALVprs?= Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: DS0PR11MB6373.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 9892dbcc-5ac8-41c4-27df-08daed3b326d X-MS-Exchange-CrossTenant-originalarrivaltime: 03 Jan 2023 03:32:53.0901 (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: An4kFQjQKfSwR+EaL9uksgjxgsiXQbUhfGm1APkx92jw1MVtvSJ2RhCTYCSsLuxsO9fyThEfaBe3pboD2E0AGg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: IA1PR11MB6420 X-OriginatorOrg: intel.com X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: DC9C880012 X-Stat-Signature: fsb5k99arx7bw8xf89uowb1itr9t7myc X-Rspam-User: X-HE-Tag: 1672716801-26222 X-HE-Meta: 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 f6OS986U 4HqRR1QVO44OKFLih8HSfGBeiig== 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: On Tuesday, January 3, 2023 9:40 AM, Chao Peng wrote: > > Because guest memory defaults to private, and now this patch stores > > the attributes with KVM_MEMORY_ATTRIBUTE_PRIVATE instead of > _SHARED, > > it would bring more KVM_EXIT_MEMORY_FAULT exits at the beginning of > > boot time. Maybe it can be optimized somehow in other places? e.g. set > > mem attr in advance. >=20 > KVM defaults to 'shared' because this ioctl can also be potentially used = by > normal VMs and 'shared' sounds a value meaningful for both normal VMs and > confidential VMs.=20 Do you mean a normal VM could have pages marked private? What's the usage? (If all the pages are just marked shared for normal VMs, then why do we nee= d it) > As for more KVM_EXIT_MEMORY_FAULT exits during the > booting time, yes, setting all memory to 'private' for confidential VMs t= hrough > this ioctl in userspace before guest launch is an approach for KVM usersp= ace to > 'override' the KVM default and reduce the number of implicit conversions. Most pages of a confidential VM are likely to be private pages. It seems mo= re efficient (and not difficult to check vm_type) to have KVM defaults to "private" for = confidential VMs and defaults to "shared" for normal VMs.