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 3879DC25B77 for ; Mon, 20 May 2024 23:42:04 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id A308A6B0085; Mon, 20 May 2024 19:42:03 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9B72B6B0088; Mon, 20 May 2024 19:42:03 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7E2E86B0089; Mon, 20 May 2024 19:42:03 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0011.hostedemail.com [216.40.44.11]) by kanga.kvack.org (Postfix) with ESMTP id 56BE66B0085 for ; Mon, 20 May 2024 19:42:03 -0400 (EDT) Received: from smtpin04.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay08.hostedemail.com (Postfix) with ESMTP id CDF66140FC3 for ; Mon, 20 May 2024 23:42:02 +0000 (UTC) X-FDA: 82140399684.04.5C47AB0 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.9]) by imf18.hostedemail.com (Postfix) with ESMTP id 396AA1C0013 for ; Mon, 20 May 2024 23:41:58 +0000 (UTC) Authentication-Results: imf18.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=YN+bN970; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); spf=pass (imf18.hostedemail.com: domain of kai.huang@intel.com designates 192.198.163.9 as permitted sender) smtp.mailfrom=kai.huang@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=1716248519; 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=cYBeXwhiajHjl0L7o3IwRndpw1VPUEu+pFUvwVjAmj0=; b=raS2uH0nd+jTIxYt3dKNK1t3+kiBWS1JcwTjSv/oQvBw+H00QGh5FZVeMEt8qR+wQarR+y 95rr6cDTAn/He8HVA4J+mOXKqnQNzXBY5287wIGrT4Grb5UDk68DQJuCP8yff5BCZWo2RO e77NTFlOzQs99B3FLTzS1xldgRvqb9I= ARC-Authentication-Results: i=2; imf18.hostedemail.com; dkim=pass header.d=intel.com header.s=Intel header.b=YN+bN970; arc=reject ("signature check failed: fail, {[1] = sig:microsoft.com:reject}"); spf=pass (imf18.hostedemail.com: domain of kai.huang@intel.com designates 192.198.163.9 as permitted sender) smtp.mailfrom=kai.huang@intel.com; dmarc=pass (policy=none) header.from=intel.com ARC-Seal: i=2; s=arc-20220608; d=hostedemail.com; t=1716248519; a=rsa-sha256; cv=fail; b=YYMVOa8TWYktlgkTFeo97C867XbzecqDutWtJVcVUiYis3mkCFVLtLBgzQfEJzZ2aQaQDU wyNJnkIfFkxvqea8EL9I/ziIeI1Prhj31AT5m6ykWcWnhwLHQgiRuuhIMyj4IsPYvhwnNv /JQh902CD3DyNosTVA68FtOyijJ2b5Y= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1716248518; x=1747784518; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=dAANT36lCbjQIDCAJNjDpak4gr8S8W2H4/XkITL97B4=; b=YN+bN9707fuSzHxU2aFUUDNObc7YkpJB+CguJtkLEyROlzsDxKTW30Kf X4FQ7qxVf0zck9EXnRcuYTJB5Pqclbvo/spIBSL9kT3dMro8/qH8E8x/a 7bSUuOKmB9B6V5og+5PcvJ+iXdnP4xTB3uYlf4oJN0LVUuXrT7Eg9w6hp MuXdTw/3oO0/ELR65iN4Araka7U6TBJA9HHP1YCyy7GtAcI/xNiKJxlz5 ifvwhmOUaicSI5U2vzApgaGEhAgfdydf1JbKYbQlV3WCAHK2TaTzGEurg b0g/EPeutPTtND9ia6oGJZMiVsNXHwdD2IK01TP1EjNY3w74luCG8Vd95 g==; X-CSE-ConnectionGUID: Pro0OykzT5K4857dBskwLA== X-CSE-MsgGUID: BOpIak+6QEqC3J3JnfgQrA== X-IronPort-AV: E=McAfee;i="6600,9927,11078"; a="23081955" X-IronPort-AV: E=Sophos;i="6.08,176,1712646000"; d="scan'208";a="23081955" Received: from fmviesa009.fm.intel.com ([10.60.135.149]) by fmvoesa103.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 May 2024 16:41:53 -0700 X-CSE-ConnectionGUID: RTf5fBjYQ7ugr4klACQCug== X-CSE-MsgGUID: eieG+HBpSACh/BWgCoMHbQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.08,176,1712646000"; d="scan'208";a="32740633" Received: from orsmsx603.amr.corp.intel.com ([10.22.229.16]) by fmviesa009.fm.intel.com with ESMTP/TLS/AES256-GCM-SHA384; 20 May 2024 16:41:52 -0700 Received: from orsmsx611.amr.corp.intel.com (10.22.229.24) by ORSMSX603.amr.corp.intel.com (10.22.229.16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Mon, 20 May 2024 16:41:52 -0700 Received: from orsmsx603.amr.corp.intel.com (10.22.229.16) by ORSMSX611.amr.corp.intel.com (10.22.229.24) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39; Mon, 20 May 2024 16:41:52 -0700 Received: from orsedg603.ED.cps.intel.com (10.7.248.4) by orsmsx603.amr.corp.intel.com (10.22.229.16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.39 via Frontend Transport; Mon, 20 May 2024 16:41:52 -0700 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (104.47.56.41) by edgegateway.intel.com (134.134.137.100) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.1.2507.39; Mon, 20 May 2024 16:41:51 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=NlytPl7HwRthXwH4Y72F00qZOGdFl7do2DLHUuQNFrsML0N1grrxXPvSbOsApNiM31wwXKm/BPwervVy5cUa6GfVHJE6adorISzrIF8u8u00ovCYRtFSuk5OKcUo4KPfR1+nqjzthlhw8KlPF26uoHaHlZToVIGsaHP2GkHUNdPaImhynMcJNE8wXr/rQqwJajK9nOd/UV49Cx5VrAYWya+C5lFbSx55nI7g7IeICcTsOU19TPIBAtgekOU/NnkHUUevP4+fU5/67/MDxylLGnpb80UHdnj85T+Yy7f+pd87SZEw3Pnkw2X3EQaWu9rAoXEmIGlNnzxFWQMYLXHrPg== 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=cYBeXwhiajHjl0L7o3IwRndpw1VPUEu+pFUvwVjAmj0=; b=Mis58fKk2lzE11wvwVjNLpqNSQ3qotLAvc8v2vZM4/9CzQQOHL4SRKDpIEovd554/OTjsL3hk4OOCtEx8SZB40yT4AaZTtd+ItxdzmF70fu+TznIWTfgl9/xzn7dxv8QnXi8VFfaQZBoAekOozR9/7dQ+zkIQ1Mm+8mvJPCPnzkxfwfp8klIIEMkq1ufwhjW8aqwn+p0jPCTPslLxxc97/Cbf32AAiqdNJ+L8ui9sXG0AmLCl31aJse8Qc29tNbZUniq/AN1kDpLaet8cUllwl7rZ5DUG4hVRkkDDn8FafeO5VepcF5972fXfErhtwjSJvi7e2jmseE49K3+/XyEKg== 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 BL1PR11MB5978.namprd11.prod.outlook.com (2603:10b6:208:385::18) by DM4PR11MB6066.namprd11.prod.outlook.com (2603:10b6:8:62::13) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7587.36; Mon, 20 May 2024 23:41:48 +0000 Received: from BL1PR11MB5978.namprd11.prod.outlook.com ([fe80::fdb:309:3df9:a06b]) by BL1PR11MB5978.namprd11.prod.outlook.com ([fe80::fdb:309:3df9:a06b%4]) with mapi id 15.20.7587.030; Mon, 20 May 2024 23:41:48 +0000 Message-ID: <1ce87335-2ea7-41c4-8442-36210656cdca@intel.com> Date: Tue, 21 May 2024 11:41:31 +1200 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v15 13/20] KVM: SEV: Implement gmem hook for initializing private pages To: Sean Christopherson CC: "isaku.yamahata@gmail.com" , "kvm@vger.kernel.org" , Rick P Edgecombe , "michael.roth@amd.com" , "pankaj.gupta@amd.com" , "tglx@linutronix.de" , "tobin@ibm.com" , "liam.merwick@oracle.com" , "alpergun@google.com" , Tony Luck , "jmattson@google.com" , "luto@kernel.org" , "ak@linux.intel.com" , "pbonzini@redhat.com" , "pgonda@google.com" , "srinivas.pandruvada@linux.intel.com" , "slp@redhat.com" , "rientjes@google.com" , "peterz@infradead.org" , "linux-kernel@vger.kernel.org" , "dovmurik@linux.ibm.com" , "thomas.lendacky@amd.com" , "x86@kernel.org" , "bp@alien8.de" , "vkuznets@redhat.com" , "vbabka@suse.cz" , "ashish.kalra@amd.com" , "linux-coco@lists.linux.dev" , "nikunj.dadhania@amd.com" , Jorg Rodel , "mingo@redhat.com" , "sathyanarayanan.kuppuswamy@linux.intel.com" , "hpa@zytor.com" , "kirill@shutemov.name" , "jarkko@kernel.org" , "ardb@kernel.org" , "linux-crypto@vger.kernel.org" , "linux-mm@kvack.org" , "dave.hansen@linux.intel.com" References: <20240501085210.2213060-1-michael.roth@amd.com> <20240501085210.2213060-14-michael.roth@amd.com> <41d8ba3a48d33de82baa67ef5ee88e5f8995aea8.camel@intel.com> Content-Language: en-US From: "Huang, Kai" In-Reply-To: Content-Type: text/plain; charset="UTF-8"; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BY3PR05CA0034.namprd05.prod.outlook.com (2603:10b6:a03:39b::9) To BL1PR11MB5978.namprd11.prod.outlook.com (2603:10b6:208:385::18) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL1PR11MB5978:EE_|DM4PR11MB6066:EE_ X-MS-Office365-Filtering-Correlation-Id: 388f4dc0-6c6b-43c6-31c3-08dc79266aa7 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;ARA:13230031|7416005|366007|376005|1800799015; X-Microsoft-Antispam-Message-Info: =?utf-8?B?bFc5OXJ2OWZEYVNpa2RWZFRsMWUyT1FoNXZWTUtXUmZFZXA0NEhmTklmWGFB?= =?utf-8?B?dThteEFnWDJGdlhnbm51U2UrbUVJWmRWMXdqNWtzZFVUMStlQ3JyWlU0OXRZ?= =?utf-8?B?V0V1N2M3aTNncVIxMG0yc2VUT1JWQXl3SHJ2SzFDMEJBb2dxWElLcHVkb2tY?= =?utf-8?B?cjVSc2JmTkZxUU1pUjVCTUhnUDd3QTM5bjYrOFdZakNEM29OelJkV2c4QThK?= =?utf-8?B?ZGdRUDh5aVVpZnB2SSs4d1dJRXFlcEpVejRydTMvUVpxRThhUkI2b3dQcm1r?= =?utf-8?B?SHNRdnFuMHU2dzEwSXNhSWdtVkQrOTJHVjNhMTlJalAvazd2c1ZidTJ0VHRx?= =?utf-8?B?bVJQYnJSR09pUkdqZktPOVc3WWttUFlvWHByU2srM054N2oyV29sdENWVUJn?= =?utf-8?B?UFA5bG1NRjczbm9FNmhjdGdDWFhnYVhEZ3ZCTTFZZE5CSmp2MkRwSUJ3T284?= =?utf-8?B?amVyYzB2WlZGbUZIVmR3NEU4N3lmUmpLdGJsWmhrMmlXLytpS0ZPYUlsbk5j?= =?utf-8?B?R1NPOWc0VjljVlhlNTRHdTlZT1pLT1B1TFhCeGZkdjZkZm1NVUgwem1XS2xB?= =?utf-8?B?d0U0ajkyWG5JL1B1QzRLdGpWL1VPTVVpY2hOU2xsRXVoYktabUFxajRzSFBr?= =?utf-8?B?RDdSZGFFaFF4S3FWd1h1Tm1oTUtieEk3K2pJTGYzZ2lRZTExOXBncytKNzF2?= =?utf-8?B?bTNwcTB4NGdrQ1Z3NnNrZmhWUUp0RDJNNEgyMWlMdGsxYklENFVaWG9pTmRy?= =?utf-8?B?VURaNHR5YTY1R1cxR25JaTZZcUloMGVXT1J1M3AvaTRYbWljam9HTThBR0o1?= =?utf-8?B?SGR0Z3JqTmNnTHNIejdQd0UzVXd5STdCdmNwZ0FGUXIrM2svTjFwMDFxQWEx?= =?utf-8?B?WXU1bWNiVGE4WGRBMzdDNGE3TXQ1WmhSL1UzS09qamVFSkZqSjNTMHQ3NHBD?= =?utf-8?B?b2lWOEV3MDlzcXI5RFJRZ21mY1c5K1VGKzRSekwvMWJjK1hSNGxnaEpMUUlq?= =?utf-8?B?VVlza0pqOW1pckZQUFFxL3ZhcGp4OHg0NXUyNHhZNTNBa0xBTXBRRW8wQVp5?= =?utf-8?B?dEhZUGFxekF0UE9oUmg5emtiYitZS0dTN0g3b3lYRHpIQmttRENHQ1B6L0U1?= =?utf-8?B?d3hNcFdCbzRkZXBIaENDMUc1SVUzZFIvSHBocXlxMjJLazE0RHF1U3gwU2Vh?= =?utf-8?B?Zm5SbFR0ZGNlWG9rcEhWWVhzWkdTUUE5TXcwNU41ZmxrUklJNTZkdmcvYXh0?= =?utf-8?B?b05NNFozWEhlYXJ2NkFTdzdhQmNPN3BrVXo1YnRFWGxlRWRCaktvWEN4TWZO?= =?utf-8?B?RXE0VGFxbnYyWlhkQW1mRStIY1g5U3Q0YlhtVDR4ZWIxd1hma0JDaHlXNlE1?= =?utf-8?B?ZkRVOE9pTEJoR2dqS2pqSjc1ZFpOQzRGQnIxWHlEOUZCNUdKanRvQUJYVzVj?= =?utf-8?B?clE2a21BOWhxdVhhMURDblFNbTRvYjZtMG9FczJaby8rTWRGMVBJeUJJODFD?= =?utf-8?B?dE1mREI2YW1WeHE0bzQ4VE4rbFZ0bEx1cS9JMWVOWkZCQzc0QWlhcThhVG9G?= =?utf-8?B?NDliWUhTUVdEd2ltdjFiNTJ4bEFpOFhxcmRLZW1CMlU5bEQxSW9pRU1yWlJs?= =?utf-8?Q?goPxjjImw12BCZgi2veNnFBGl7Sl1m1okVMXHGb0KsaU=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BL1PR11MB5978.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230031)(7416005)(366007)(376005)(1800799015);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?WjMxT1lGWVVUSlFIZEIrejhvcWJRc1U3QXNOL0xTUTVhdmxqaVJKYkZTdDlz?= =?utf-8?B?U2hJS1d5M0twZkFqakRuSEU5dDNmdmZWR2kwYXBtRUpaem90Sm9vRjJIMHRo?= =?utf-8?B?blBTQTVTck5OVTZzZ05lclFMVXB6U0FaaGhMM0l3ODZ1blBnZFJ3a3pKY0w4?= =?utf-8?B?QlNlSDh4QVRIbWpSQVlSMHY2MW1abGRsVng5ZHcwaE5FVFRFN1lLNFFPV1I3?= =?utf-8?B?dFVDUUJyanJZYmFFNUN5MGRxMkdEWkFXV1JmTUxIUTI2eU44cDc5U0F6cEdH?= =?utf-8?B?cVlSMlc1S0twZDE3SW1BWXM1U3RNdGc5Rk1mRk4vaHRURkR2NU9hSmVKTnht?= =?utf-8?B?NCtDaUZseWYzSWUxVzFzVi9JbVY3WmNXVDQwOWpMeC9iT2ViNFQ5S2VVSnFo?= =?utf-8?B?VlQyMERmM3RBT3VWWmZJUjZJUzh1V0VoYTYvS3NOYm5aVjRqbnVYTEZuekZM?= =?utf-8?B?cWJ1ZURRZURlbW5Mc1FVQVRBOXhMODRieDFUM3RDczRVbFBpUmdyb3pGOHli?= =?utf-8?B?eWMwSFFRK2R1S0NFTjZHamUrYlIxWGFMWU1paXczTFBVQlZjVmEzV2t5cXg0?= =?utf-8?B?KzdkZjdiRUVuZ2U2eER2TUZjMkhyckJxTFMramNiL08rQ0hWTmxyZEJmQ3M2?= =?utf-8?B?SXBlNzQ0MTFicmdWUXlYeDBNYjRZOWsxVit4TnZPcS9pQTl4MTRrMUxTNEY4?= =?utf-8?B?emVPb1JxTzJLNElWZyt0ZU8zTmtRVkF6YjlDcGFpN1BIbkc1a3JNOXg4bXpj?= =?utf-8?B?ZmtxVy9CUU5Md0VpbHMyMXk4bklTb1V0Wm5CL3ZWNi9lK1ZCTjd2eWFUSndR?= =?utf-8?B?QW1IeWJXT3BNWWRFaTZUcWJDNEwvRHpYcUdnSHdZVnN1QzBleUVBb3lyWFZw?= =?utf-8?B?djhOV1diNGlMNUhoUkFqcWF5WjY4VFd3R21zcCtHK3ptNzN3bzFnZGxVOXo1?= =?utf-8?B?RlVndkZwQXdvQTB6SHp5bzZMVHQ5ZDk1MFpGbTFuUktSS3Y0SlVpWnU0ODZO?= =?utf-8?B?TmdaM0l6YTBScFpBdGtKdmNwV2YwTERoU200TGZUK3dMNWt3ODR1TzlEVE00?= =?utf-8?B?OStTTHFUaENZUlY0bHBabDlkTG4zdXphM21YRFB1R1pRd3p0WEsxeEp1clZI?= =?utf-8?B?VEt5cjhheTRXT0FDMUsrazBoaTRIcU9RUkRteGVyalJ4WjRzMk5na200dExp?= =?utf-8?B?RDBrdHhjR1VMZkNiWUdpZDM2RmUvYVBhdHhEZjJVUDV0Y2JhL3JrRXp1SFZr?= =?utf-8?B?QmVtYUhVOTI1TDV0Vk9uM0dFRUV6Wm9mNWxNYXZEMFpSU0R5aFJwT1pod1dB?= =?utf-8?B?MVlHVkJIbFE0cUJVOHNaMWdMZW1OTklpQmhlK1BRZS9xVlpuRlM0SWNSc0xT?= =?utf-8?B?RjNiQTRHRkdkZzJrUThsb01GS0VXL0VydHdIcUgxSjY4VmI2YzBXT0gxVjV1?= =?utf-8?B?WkY4SXhGSGNkMnpoaTR5a1ZFVTN4ZFBUdXFLYXh0dU94cVZIUWJaV2lVN0pq?= =?utf-8?B?bFc0THVVNEpnZk1GM0tCUjhYM0o2WXNubDFEK0hQcGR5bDdjN1dpTUdCcEFt?= =?utf-8?B?MWVUN1pWMVllUW1jQ2tXaUdydFEyYWZQamszdWE5VEZYOG0zdVB6eFk2d285?= =?utf-8?B?N0h5RFJmUmhjMUg0RWpwY1VzNjhHZjdYVHEvR3NVUmJnMDF0NHk2RTdOWXZl?= =?utf-8?B?U01TUi9FWmlyZW0wWXZHY2NURk9naXlZWW9kS3FYNlBxeFZXMlF1azlGM3hU?= =?utf-8?B?YW85cmI2QzJmdVlKNEJqVXZVQ3ViR3g2aStmM25EVWt4MXh6ejBUS2h6S3hi?= =?utf-8?B?ekxuaUxlMThXcUc3M1NYSXk2QzQ0RlBCUE5mOE5PZjMxdmc3MjNqbktGV2J0?= =?utf-8?B?YnhtZDVJWjJ6em1keEN1S2ZlVkRnKy9hZmFsSXFreHB3WjhPODNsTTlnTWNQ?= =?utf-8?B?bmZGWFpSYUoyVG1PNE9xd3ZWeVJsMVptWE5OU0djVWp6Umx4N1hramhjRUFO?= =?utf-8?B?Q2xWVHluOEU5RllpdnpCcGNiQTd6VXFWaHhpL000UlpicWltTHpZc2NJeUNp?= =?utf-8?B?ZHlTZTlId0kzc0xxeVlBci9QSWlvYjkyb0FyaDExSldQWXM5MU4rWExEZVJv?= =?utf-8?Q?JsnPRCsjCEmD5aI4M68AoZvf0?= X-MS-Exchange-CrossTenant-Network-Message-Id: 388f4dc0-6c6b-43c6-31c3-08dc79266aa7 X-MS-Exchange-CrossTenant-AuthSource: BL1PR11MB5978.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 May 2024 23:41:48.6717 (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: OkKtdKjS7jT0Wu+cf6ZoSyRCR8d2b4ygh1oxqE0pZrZYIVERNAlrlhrUAEvOy/oIwY79ubshrZBVEp07h/ltZw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM4PR11MB6066 X-OriginatorOrg: intel.com X-Stat-Signature: mny3hmomzwfopir3zowt5y4tfanw63ko X-Rspamd-Queue-Id: 396AA1C0013 X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1716248518-56733 X-HE-Meta: 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 AIHrYS5n 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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 21/05/2024 11:15 am, Sean Christopherson wrote: > On Tue, May 21, 2024, Kai Huang wrote: >> On 21/05/2024 5:35 am, Sean Christopherson wrote: >>> On Mon, May 20, 2024, Kai Huang wrote: >>>> I am wondering whether this can be done in the KVM page fault handler? >>> >>> No, because the state of a pfn in the RMP is tied to the guest_memfd inode, >>> not to the file descriptor, i.e. not to an individual VM. >> >> It's strange that as state of a PFN of SNP doesn't bind to individual VM, at >> least for the private pages. The command rpm_make_private() indeed reflects >> the mapping between PFN <-> . > > s/SSID/ASID > > KVM allows a single ASID to be bound to multiple "struct kvm" instances, e.g. > for intra-host migration. If/when trusted I/O is a thing, presumably KVM will > also need to share the ASID with other entities, e.g. IOMMUFD. But is this the case for SNP? I thought due to the nature of private pages, they cannot be shared between VMs? So to me this RMP entry mapping for PFN <-> GFN for private page should just be per-VM. > >> rc = rmp_make_private(pfn_aligned, gfn_to_gpa(gfn_aligned), >> level, sev->asid, false); >> >>> And the NPT page tables are treated as ephemeral for SNP. >> >> Do you mean private mappings for SNP guest can be zapped from the VM (the >> private pages are still there unchanged) and re-mapped later w/o needing to >> have guest's explicit acceptance? > > Correct. > >> If so, I think "we can zap" doesn't mean "we need to zap"? > > Correct. > >> Because the privates are now pinned anyway. > > Pinning is an orthogonal issue. And it's not so much that the pfns are pinned > as it is that guest_memfd simply doesn't support page migration or swap at this > time. Yes. > > Regardless of whether or not guest_memfd supports page migration, KVM needs to > track the state of the physical page in guest_memfd, e.g. if it's been assigned > to the ASID versus if it's still in a shared state. I am not certain this can impact whether we want to do RMP commands via guest_memfd() hooks or TDP MMU hooks? > >> If we truly want to zap private mappings for SNP, IIUC it can be done by >> distinguishing whether a VM needs to use a separate private table, which is >> TDX-only. > > I wouldn't say we "want" to zap private mappings for SNP, rather that it's a lot > less work to keep KVM's existing behavior (literally do nothing) than it is to > rework the MMU and whatnot to not zap SPTEs. My thinking too. > And there's no big motivation to > avoid zapping because SNP VMs are unlikely to delete memslots. I think we should also consider MMU notifier? > > If it turns out that it's easy to preserve SNP mappings after TDX lands, then we > can certainly go that route, but AFAIK there's no reason to force the issue. No I am certainly not saying we should do SNP after TDX. Sorry I didn't closely monitor the status of this SNP patchset. My intention is just wanting to make the TDP MMU common code change more useful (since we need that for TDX anyway), i.e., not effectively just for TDX if possible: Currently the TDP MMU hooks are called depending whether the page table type is private (or mirrored whatever), but I think conceptually, we should decide whether to call TDP MMU hooks based on whether faulting GPA is private, _AND_ when the hook is available. https://lore.kernel.org/lkml/5e8119c0-31f5-4aa9-a496-4ae10bd745a3@intel.com/ If invoking SNP RMP commands is feasible in TDP MMU hooks, then I think there's value of letting SNP code to use them too. And we can simply split one patch out to only add the TDP MMU hooks for SNP to land first.