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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 00785C46467 for ; Mon, 16 Jan 2023 08:24:21 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232288AbjAPIYT (ORCPT ); Mon, 16 Jan 2023 03:24:19 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47536 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232035AbjAPIYP (ORCPT ); Mon, 16 Jan 2023 03:24:15 -0500 Received: from NAM10-MW2-obe.outbound.protection.outlook.com (mail-mw2nam10on2051.outbound.protection.outlook.com [40.107.94.51]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 9CA081205D; Mon, 16 Jan 2023 00:24:13 -0800 (PST) ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=T6o7wAwhtDNzKqYSnWHElxrdyYeq78RypF4TginRQqu+8M5mkfQ5nMTSPZH6dUxNMK1+abwmNf+NbqpuSkhGkK7569IYjIfuWvR8kJc5Be+U2vQzZnr8NNT9BjbD3jOOa6/iRHtW6VCcB6CpDtemXLHn4imDLryAIeRTNqOy9Boo3gprLM/RI6uNE5+FdXL2oXKn/1qaWt5gxYzXB9JG1fQbZl6gapc3z7h4t49vW9NWmhXu+y060LyAXTnnghyUPuPAS6zlo5yTlv+ktTElELYxkQ8lHhsxgqei8EQ1ma2FlVWOddNeW+7zrZONgcCCBgiYSUkk5aET2w1TU/CTaw== 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=iCA+WWwt4p6a0LqEZaPpFYF4XG6uToQEmvNMAsfgPzQ=; b=VcXmbp2PFaRbMJbKQO35iMXLJ1uzvLlXUD4qnrpzZsANx1IFxY0opjtpYDw+fUGp2u20Ln6tp0Ftz2Kk2XEwsvlo6TLZZAj1Cw7KLlwPAYA4GT+BW/UhEtF3X683LQjIjW7ot28/8fBL1f20+HEHRhxc4ZUMmJmpv5/wmIKBHr+m654m/nbBPJVkjbx/c4JpnrZZ4O2k9R5I3csZpa7DOxdsPCdAA6HT6Rs8X5b8nW1CuEaFXWAotiu6bdqFnqKSig9T7fg2wLO9ojcmuKJSoiaynpasIa6FJ0kHTXox9fEApRAgwRc6WpST8Ra6KA5yVbNmqOZ3XuxUBIFSah1miw== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=amd.com; dmarc=pass action=none header.from=amd.com; dkim=pass header.d=amd.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amd.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=iCA+WWwt4p6a0LqEZaPpFYF4XG6uToQEmvNMAsfgPzQ=; b=eJ9A/XDDTNQxzIExUhSGy4OZon2RlDvbbzfcB45ucEBWEvatmbgQPyK1wk/Q7y/bxvfB9NcyDVMmNHZ9ORbCbFNFL9H4+ae1gXShhB+KBlnYDwdvNeF5NjQg6qyIjpmZ3rvpbCyQELGjlsjsf2PTX+6Ls0EGoft+9CyaBcI4CXU= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from DS7PR12MB6309.namprd12.prod.outlook.com (2603:10b6:8:96::19) by PH7PR12MB5595.namprd12.prod.outlook.com (2603:10b6:510:135::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.5986.23; Mon, 16 Jan 2023 08:24:10 +0000 Received: from DS7PR12MB6309.namprd12.prod.outlook.com ([fe80::8079:86db:f2e5:7700]) by DS7PR12MB6309.namprd12.prod.outlook.com ([fe80::8079:86db:f2e5:7700%6]) with mapi id 15.20.5986.018; Mon, 16 Jan 2023 08:24:10 +0000 Message-ID: <4bca96ee-3665-5503-bb88-baae98e700e2@amd.com> Date: Mon, 16 Jan 2023 13:53:56 +0530 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [PATCH v5] x86/sev: Add SEV-SNP guest feature negotiation support Content-Language: en-US To: Zhi Wang Cc: linux-kernel@vger.kernel.org, x86@kernel.org, kvm@vger.kernel.org, bp@alien8.de, mingo@redhat.com, tglx@linutronix.de, dave.hansen@linux.intel.com, seanjc@google.com, pbonzini@redhat.com, thomas.lendacky@amd.com, michael.roth@amd.com, David Rientjes , stable@kernel.org References: <20230112084139.12615-1-nikunj@amd.com> <20230113135326.00006f06@gmail.com> From: "Nikunj A. Dadhania" In-Reply-To: <20230113135326.00006f06@gmail.com> Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit X-ClientProxiedBy: PN2PR01CA0172.INDPRD01.PROD.OUTLOOK.COM (2603:1096:c01:26::27) To DS7PR12MB6309.namprd12.prod.outlook.com (2603:10b6:8:96::19) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS7PR12MB6309:EE_|PH7PR12MB5595:EE_ X-MS-Office365-Filtering-Correlation-Id: 8c5eebdf-429a-4833-b79a-08daf79b0aa1 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: z1GPCzpMJWV2LQed2A39Exrt0bwb/gTGnKNJMv3t3zL4jTccevnDBAw0vXNRyQVB8MEalJQv+GdLEj2+fMfwEuh4T2pojIp27wfvoWyzUeg2JulDVrpOE3Aszqx60PblF5HYIw1sw22ceuI6ELt5JBN3yHjQaycDkSRc3qMbgow+jUWypPaaaW2nZA7HM/c/Ya/RW8OhMJOox1TBQas7RBDeyNErFeKATrEg4EIxUah04Pi+k9OFTRkMe0/0UuoM+0k0fAsw5kB4ghjCjZDrwKtXoEyOSC0stbQun6q5OJDlHS+yok61ZNS1Hrnry9nkqVV37wlhRUEZtliGTCTQiBY/AMi0CPhJ+tUifjUJxPsqbqB3IT2AjnNpJHnlpL81LQsxPx+9kfvx0i5du9ZBDKg7fbvrSlufCJz+1//I4oy9ga5Ed+iqiAN2wEJaHKQPGyHv5qms2Nr5+XNw5TtAwm9xAQbB84dgnB5KYjso60mT9gwCgiqcBl9u4t0RKxKQcT4Lfx6MUxznnR2V+J18DpYyhHfq7xMFy4TqpTxdgMsCdGJnAzoPPfyjnkhQEOwnPhYh5I5NUc3mNxhMnXxO6UJmmm7sugVhX2rKCxegnCU3M7IRq9Otl1zWvzRbVs5e6xTf65RgQqlWL0v3FZA11pYYQz9/itg66iGhMVL9i5J1iZKC8D7ZQKjaVvEuXqNsUPI4LAZmkS2lDBHd1rEfKl/MqRPARB35699VzNN5dqdNpzmbUxye8gVw2i/AQ4Hwe4jU/g2eyD5G4HwbxBiWGA== X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS7PR12MB6309.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230022)(4636009)(396003)(376002)(366004)(346002)(136003)(39860400002)(451199015)(36756003)(4326008)(66556008)(6666004)(66476007)(66946007)(5660300002)(41300700001)(83380400001)(26005)(8936002)(6512007)(186003)(478600001)(6486002)(966005)(6506007)(53546011)(8676002)(7416002)(6916009)(316002)(2616005)(31696002)(2906002)(38100700002)(31686004)(45980500001)(43740500002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?anpLVWVYeXZLcXZlcGZ1ZjlQeW5hQW5BdUpWb2hpWnA1ZVNra212VHdxUUZq?= =?utf-8?B?cjZaeldKeElncGFSQWJRNXJFZXQ4d2RXYURISWpseFl0dmp0UlNnazNlQUxv?= =?utf-8?B?Wkh3dGx0VlQyRmNKaVU5WVhhNFc5R05EOWdYMnZSRVV1K2RPQjNXdGtZRmVp?= =?utf-8?B?SHdTZW82dXFHTnZkd2lKSmNPdGg2bEhESXlQeVBzTHZUczBHQlpzWEdmUHln?= =?utf-8?B?VTNQZ0VmcVBsSVdGOEVqdjVaem5sMlhQYnlCdXdsS00yN3ZsdWNNQ1FUZWRh?= =?utf-8?B?Z1grYUhvbGE0OUpXdlVjVmFCUVJ0bGhlL0h4alBEcWsrZXR1SVBXeVUwZ1dI?= =?utf-8?B?a0k2dWdRcFE3bkI2VjV2UFltcm14QTcwSHdtZENJcHd0M000a2RXeUJyRTN2?= =?utf-8?B?VTZuUXlNYnArQVJ1aVYrTEhzUVlXR3g5WmJLZWlMaEk5VHF0b3E0ZHJnZWg0?= =?utf-8?B?R2w1TktqNURIZy9sSXJKWC9DcWducmtEdnhsVGkwajBXdDdhdVVmODlQOGwy?= =?utf-8?B?MXdsQ2FtNkFQVnUyelFjRGNYV1RvcHZTdld5YXJFY3pMTDl3M2R4NjlXWjNp?= =?utf-8?B?eXFKVVpFL2x4TTNQdnNOK0FqNWdjVU1CeVFXTXBBM1d0R3FmaFY4RUxKcDE1?= =?utf-8?B?TXQxZ3pEeFFpdUNzV2ZleWM5RmpseGtFdms3c0xzTWRHR1IxcSszSkE0dkpN?= =?utf-8?B?WG5vMDN4Q3gvZE5hNTFFbVdya3d5ajBjNjZCeFlGZnJaRldiN2pjUzNCQzEx?= =?utf-8?B?TEViSmEyQWFVSGhub1QzbHVISTd0ejdZeEszM0YvWE9zTzFFVWJhTk8vb2ZS?= =?utf-8?B?bS9WT253eUhZVDJpT2ttQzRZQndFbER6Qk1yV0NrMXA0YTlWeHRvNHFPOEMx?= =?utf-8?B?SGM3dERkZWJySk1GNUxZa3ZUUnBtdEJFaGwyaEV4aEdsM0dWaVU4VXkvbmtD?= =?utf-8?B?Q3g5aEd5ckNucnlMRkcyQi9oczFEbS9YQURBU3pRdnNPR1FvNWhDcmVzSWFK?= =?utf-8?B?OFhKeVlSUmhlOTB0NDJzanYvNFY1K2dBMHNEVWFYa1FtSDhzcUhaelpEckJl?= =?utf-8?B?dEJTYWZoaFhaYnhJMkNpcUllc2RydDAycnRaU3RiWmVmTU8reTBxYjBMdkh6?= =?utf-8?B?bVVRQlA2anVjOERnSU9PZUxseDY5QjNhNE43SU1aSk9BaDFKaDV3WElxT1RT?= =?utf-8?B?cE44KzQzeEZ5dmU1L0E1RXR6M3VTMm5udDdjdDdtMkFyZzFnbDJmVnFXTTZM?= =?utf-8?B?UWJwZENHc010USs4ZDdzaEhRUjFRU3RpYS8zRjcxL2tJamVkeE1HY1hHK1BN?= =?utf-8?B?ZSs2TXl4ek1wWHU0MUkrWlQyWk9UYUI2L1JWNUNJNG5KN2d5OWhGc2tyTUtR?= =?utf-8?B?eTQ5Z1VFUVRPNUNvQmpsdGVEREMydStWT0xEUVE4enFvZUdJc2w4YmM0VTUz?= =?utf-8?B?VnRUS0s4aXNiTXVXZ0RNV3ZNdXRvV3BuYWk0Y3N0U3N1bE14K01kdG9GbDZS?= =?utf-8?B?TEcwdDlMckZSOE02S2dtWVM0c2pqZ09DRkVidlFSV0xwWHZLdkNydUxkeXM4?= =?utf-8?B?Q2lKQTFXQzF4NHlpZ3MyMWtjR0s3V0QwVzNQWXVaaU1CbjhCY2p2WEFMREFT?= =?utf-8?B?YkZ5SkNpdzAxZmRGOU12WklMLzM1L2JOd0RaZFZITTNGMExmSGJpZTRHSFlt?= =?utf-8?B?Q1F4elAzY3FNRkpPakg4ekVYWHpzYmkyek1xbWgvNHZtbjZXL3d1eDVqb1lF?= =?utf-8?B?ajNSUFRFT01kUTJZbU5sRTBRa0NURVJndUdHK3JBVnNoa0NuNFdRblRIRk5i?= =?utf-8?B?TmlJVUZ4blZ2Z0ZHRHM0aGZsaDdPOW5YWHFrbTBQaHhtSUMrM3d3a1I2ZHlE?= =?utf-8?B?bmliZ2V4em5UYWpYWmVNWU1GT3k0aVBXcU9DajdCVGFkSFNHVjlHZE9JN0hv?= =?utf-8?B?MGIwZWVQUHlJZ2hobDJOZWFVMUVwT01lL2VCVi9HSm95cE5Hb3RTdWUwbUxz?= =?utf-8?B?RW9HWWRkNTRVOFVMUjMwNnRsUkV3aTJ1V2ZkcWhscmRveEdrLzhZdTVwMkZY?= =?utf-8?B?OVpJRDJNWDE5Z1ptV1p0TlZ5Uk5wdzIvb29hRkhyTGZORGFGbUwxamR1Tk5J?= =?utf-8?Q?l0X9nKNjUGL0jQxcT/lEkeXOx?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 8c5eebdf-429a-4833-b79a-08daf79b0aa1 X-MS-Exchange-CrossTenant-AuthSource: DS7PR12MB6309.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 16 Jan 2023 08:24:10.0626 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: JcJVlXBbFgatd+NOLRIESi3BxZA0gvutbhIf3OaI6kNTc+nMktpQuIkGUJaeMN/YE8R0TUMASpCmfP+nZZlWuQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB5595 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 13/01/23 17:23, Zhi Wang wrote: > On Thu, 12 Jan 2023 14:11:39 +0530 > Nikunj A Dadhania wrote: > >> diff --git a/Documentation/x86/amd-memory-encryption.rst >> b/Documentation/x86/amd-memory-encryption.rst index >> a1940ebe7be5..b3adc39d7735 100644 --- >> a/Documentation/x86/amd-memory-encryption.rst +++ >> b/Documentation/x86/amd-memory-encryption.rst @@ -95,3 +95,39 @@ by >> supplying mem_encrypt=on on the kernel command line. However, if BIOS >> does not enable SME, then Linux will not be able to activate memory >> encryption, even if configured to do so by default or the mem_encrypt=on >> command line parameter is specified. + >> +Secure Nested Paging (SNP) >> +========================== >> + >> +SEV-SNP introduces new features (SEV_FEATURES[1:63]) which can be >> enabled +by the hypervisor for security enhancements. Some of these >> features need +guest side implementation to function correctly. The >> below table lists the +expected guest behavior with various possible >> scenarios of guest/hypervisor +SNP feature support. >> + > "guest needs implementation" seems a little bit confusing. I suppose it > means the feature is mandatory for the guest. That is not correct. None of these features are mandatory for the guest. The hypervisor can enable this feature without the knowledge of guest kernel support. So there should be a mechanism in the guest to detect this and fail the boot if needed. > If so, on the second row > guest can boot without it. Some explanation? In the first and second row, HV has not enabled the feature, so the guest should boot fine irrespective of "Guest needs implementation". >> +| No | No | No | Boot | >> +| No | Yes | No | Boot | >> ++-----------------+---------------+---------------+------------------+ >> +| Feature Enabled | Guest needs | Guest has | Guest boot | >> +| by the HV | implementation| implementation| behaviour | >> ++=================+===============+===============+==================+>> +| No | No | No | Boot | >> +| | | | | >> ++-----------------+---------------+---------------+------------------+ >> +| No | Yes | No | Boot | >> +| | | | | >> ++-----------------+---------------+---------------+------------------+ >> +| No | Yes | Yes | Boot | >> +| | | | | >> ++-----------------+---------------+---------------+------------------+ >> +| Yes | No | No | Boot with | >> +| | | | feature enabled | >> ++-----------------+---------------+---------------+------------------+ >> +| Yes | Yes | No | Graceful boot | >> +| | | | failure | >> ++-----------------+---------------+---------------+------------------+ >> +| Yes | Yes | Yes | Boot with | >> +| | | | feature enabled | >> ++-----------------+---------------+---------------+------------------+ >> + >> +More details in AMD64 APM[1] Vol 2: 15.34.10 SEV_STATUS MSR >> + >> +[1] https://www.amd.com/system/files/TechDocs/40332_4.05.pdf > > Probably update the link here as well. Sure. >> diff --git a/arch/x86/include/uapi/asm/svm.h >> b/arch/x86/include/uapi/asm/svm.h index f69c168391aa..a04fe07eb9a8 100644 >> --- a/arch/x86/include/uapi/asm/svm.h >> +++ b/arch/x86/include/uapi/asm/svm.h >> @@ -116,6 +116,12 @@ >> #define SVM_VMGEXIT_AP_CREATE 1 >> #define SVM_VMGEXIT_AP_DESTROY 2 >> #define SVM_VMGEXIT_HV_FEATURES 0x8000fffd >> +#define SVM_VMGEXIT_TERM_REQUEST 0x8000fffe >> +#define SVM_VMGEXIT_TERM_REASON(reason_set, reason_code) \ >> + /* SW_EXITINFO1[3:0] */ \ >> + (((((u64)reason_set) & 0xf)) | \ > ^ > One extra space before 0xf should be removed. Sure. Thanks for the review. Nikunj