From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from NAM11-BN8-obe.outbound.protection.outlook.com (mail-bn8nam11on2041.outbound.protection.outlook.com [40.107.236.41]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 7EE851E833A; Thu, 27 Feb 2025 10:25:38 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.236.41 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740651940; cv=fail; b=b3eG7xX+Vv16rI9ZPJlQtO99P7Pzx+T5dGg5G0gsMeyCTIAoJ99Bsc1IWNXwHSD6Ql+eSAEl+RyiaHrTyPnBwP2aSvAUKgQvw/DwkO9O6j6CIObUoyL5qUHERpsTX8/xvydsuaXLdl0Io0C36YxWTmhCt6Ohu9SLxJNEMWasRn0= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1740651940; c=relaxed/simple; bh=XZEMcfAdwqw//Yjbcy2CMBPhCKNzvDnjskhogBGnVUs=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=NgL5WdYHQ2J7EJmAQo/rbyRpKJ9pJqCgKsPCbYsK+ErBKIgM3xByTAkrcu/DP7qpLvR2zQeI1OlErvtskpfl1YThy4mGQ56qV2gpYEHfu7VrKDLpdG0rMNMH0xQ885PzTGxE4n+omJ0A84nnxqeUqTJYYAUheEJp/76bXxNxnVQ= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=DoCokJnO; arc=fail smtp.client-ip=40.107.236.41 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="DoCokJnO" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=hIN3OKvzMniukEyFOMS7xlZtbVgYBy11jeHOMrH6Bd7VNMfFoBFFeM78gv1uJGDLZYWil2l5LvGY/pETImT+G3Y2QsRY6ooCAQ6TDEx3+zs2Q7MRFu9Hc86QzDbn9k8yIGfiAf9OE7B2awfwTpqea78G9k9IefpyrCWW93q6xAZXKxxa0WRvQe/4BR3rtAnIzuUNhAkaXRvcsM0JtKzFNNWr/s1DH5DTsn4nb4SToVdW3wZ+64mOMLaOa8PswDXYUSOeF3EghWixSY/BKHklAQbbvoBeNzcj8a7/IJoxvVXpYZmuFMBTNTy/sy7eK9xmT0s5fwZ7yQIFgQ5NuuiUgA== 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=WUcKX7t4fY70lPY7/5v+W/dHZHvlNzXZarnsAEa0Tao=; b=nd2IeedifKkKf5w49Px4aoPWa8L06DzDTHWFVxmw0Z9UIy/7VxIJpzFHRqZ6pvHTsmlqfmPtXXE3CKqwLB3mMR63n2mgAgE+OQQQhneZO9Z8s0Uv9gqeBjGcigNFzTKD5VVWbqTiRiLsCb6B3jgDiknhdgKjTenPg0vZVN560XFfk4Qvx2oMfZo+4IAgTkvg7DF2H42lELueJoYnRdfWX8k3Wk4NdGEao7104Z1k4p2QCJRUKp7kNsDA5r0H0a1nd373DtwqdIypQ8/SD7wjnZC2p6myVp9U/S7kXvxYkWxAd+5L2V83vqpD7qdmDMzI5Gv5Zmlm7bQPpIo/3RNYXQ== 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=WUcKX7t4fY70lPY7/5v+W/dHZHvlNzXZarnsAEa0Tao=; b=DoCokJnO70buX2lD/cD3v+Lxob/C6A/y2i2wNI4SiTWgVUgufxDNGgLs5JbhFa0fTYMnZ7an+dnSCqj2/nI+p9HLZFrTj+1WdMvOSw1Ww/SnFGKyS43SUhBZt8xsXcm3Q52ZdQkMNQjjEh4rr2gQvT9zFW+/I22CxZ3VBPUWlSE= Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=amd.com; Received: from IA1PR12MB8189.namprd12.prod.outlook.com (2603:10b6:208:3f0::13) by DM6PR12MB4329.namprd12.prod.outlook.com (2603:10b6:5:211::9) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8489.22; Thu, 27 Feb 2025 10:25:35 +0000 Received: from IA1PR12MB8189.namprd12.prod.outlook.com ([fe80::193b:bbfd:9894:dc48]) by IA1PR12MB8189.namprd12.prod.outlook.com ([fe80::193b:bbfd:9894:dc48%7]) with mapi id 15.20.8489.021; Thu, 27 Feb 2025 10:25:35 +0000 Message-ID: Date: Thu, 27 Feb 2025 11:25:31 +0100 User-Agent: Mozilla Thunderbird Subject: Re: [PATCH v2 04/10] KVM: SVM: Don't change target vCPU state on AP Creation VMGEXIT error To: Sean Christopherson , Paolo Bonzini Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, Naveen N Rao , Kim Phillips , Tom Lendacky , Alexey Kardashevskiy References: <20250227012541.3234589-1-seanjc@google.com> <20250227012541.3234589-5-seanjc@google.com> Content-Language: en-US From: "Gupta, Pankaj" In-Reply-To: <20250227012541.3234589-5-seanjc@google.com> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: FR0P281CA0121.DEUP281.PROD.OUTLOOK.COM (2603:10a6:d10:97::19) To IA1PR12MB8189.namprd12.prod.outlook.com (2603:10b6:208:3f0::13) Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: IA1PR12MB8189:EE_|DM6PR12MB4329:EE_ X-MS-Office365-Filtering-Correlation-Id: 2d05e652-7524-4772-09cd-08dd57191264 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|366016|376014|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?cTlUWGVpOXc0Zjh3ZlY3NGhBNlBkUDhUaDRxSi95NlhCRG1DS3ExbmFPRjI3?= =?utf-8?B?UlBTa3BSd3JMOW9ZU1dDWWFuaXYvSnFDb2tjMUhQcnZaR0lkZWpkM3o4YWtl?= =?utf-8?B?S0ZZK0RlRW14bnZVKzFkTWpEMVB0Q0cyRzd3eEFReFY2Q2k2WklhcndHcWlp?= =?utf-8?B?SHdPS0dIbGFTeDQ3TGJuQ3dUd0pFVVhFY3IvbWZnS0l3TXJzWXhGMEZLSldO?= =?utf-8?B?N3pwaE1TeXJPQ1hvTENKKzFhY1NQOTlXN3huczIrV1V2bkdTYUxWQmFxMEVX?= =?utf-8?B?cDJSdW4yVlNXQUVPZTVyd0FTaGd2b29BRXpRRjQrRzRNa00rTTd2OE9sbExq?= =?utf-8?B?cko5amJxQ2MvWEpsYVJSWVVlUXAzQU1yNk1TUnp5MUNtZStrY29aZk81cHpO?= =?utf-8?B?aHBaN2RHRnZqYUxlWGFMYlVmL1p2T1M4K0RNcjRjeS9HV09LeGw1eHNjMW4v?= =?utf-8?B?RzR1K3NTOFVHelZjN2M0dUc2RWFGYmdsb0tOakpCTlBPUHdNZmUzZGN6MXhS?= =?utf-8?B?dVlpdXpuVnhtb1ZiUGtsR1BjNEpUc2FmMktYVTAzMitLRjBaOVRPNFFyY2Za?= =?utf-8?B?ZDdFNzZzUWZZS2Z4V3cxWnFmc3NTUENDKzNmTmhKdE1UdG1GMi9QVDhCL1B2?= =?utf-8?B?Q1lEMmZlUmgwMjU5ZVBSdTgrYzBEb21nZTU5dlp2VTRtSERSTDJkOGJpdzgx?= =?utf-8?B?SENBc2UzbGxTVC9HN0NaZ2JKWEVRb0ErbUNveXlQUXE0S2tHcXNIZFM0SmFs?= =?utf-8?B?QUgwa2lWSlNlM25kVytTRnA0clZQWERmVXhIZjZrdVhEZGhOSXBIcHppU0hz?= =?utf-8?B?MnVHTUc4UVdOVXV1UmJEUzV6RUFxc2I2cXVzWStnTkJqZ2h2YURlYkJBelRo?= =?utf-8?B?STN2WTBMRE9FeTViYmJLWkMrVGdKT1RRQ1ZXOGpSMXMwbUJJdEM2Vm9lQ1Ji?= =?utf-8?B?b2M4ZjBKb3lkZyt2VGNtcVQ2RURrL2xqTUJMYnF0SHVrN0hGcmF0NnlXeXdw?= =?utf-8?B?ZmRsR0VDRWxhOEl2aitOMzlZLzQvUjYvd3FsR3Z1VDVzanNiV3pxOXFDK09G?= =?utf-8?B?Tk0wT01wbHVmaGtXT0dmSXc3ZVZvYzFxRC8xZXN5U1VYR0JaempTVVRZYzJq?= =?utf-8?B?Y210Uk04eHZScnV0bFd0VHhpd09VRXJobmZGOXlmOW5ZaDVKQ3BxbmE5VzNJ?= =?utf-8?B?YitkNFlXdURsczhHS09rTGo1K2N2YWlBQmZwSTZCdTBiR1RPM1Z6SDh2bmdp?= =?utf-8?B?V21IbGJIV1lxOXBzMGtRUW4rRlYzUm9vMGk5Q1h5ZzJHY3dOdDZtamo1L3BV?= =?utf-8?B?UzM2QjFWZitLQTRuVkNxNnZrT0U2akpySk5penFSa0w0OGJZNWpmNk96bWVs?= =?utf-8?B?QSsxZ1FzOVN0bVE5c1Y5TVRiL3F2bVVVKzdUSU5NVkVEeXQ1dExhNnYxVDkv?= =?utf-8?B?QjFQNENDUWVKRnRKTFhVaW5kZC84T0tzVExUcko4QSttc0tmRTZtKzczT0NM?= =?utf-8?B?VUFMWTAzVmpPeUJKV01UelNiL3VhVitMaDF2c3Y5d3RCNm4yakluZ3VCVmh0?= =?utf-8?B?UGJicFRvbHBKcnZ6Mi92MG5YS3puYUZLdnBobk1lb01kcmZmb1FBc2FXWFla?= =?utf-8?B?UlRwM2t4VzExYnJMT3FHTTB1dmRDVmlxSVQzcmowTW1jSG9aOXRSaW55dFhU?= =?utf-8?B?WThXMDcxZHQvMlBEUkxCczhBUGttUm1Xcm1pYkF6V2FtYnBveCtkcjhvTmNS?= =?utf-8?B?aHpvb00rZHRLekFTaVM5ZjVLaGFBTWVzS1Q5YWtRVjFMcmZQbXdpZEdGaEdM?= =?utf-8?B?SHgwdlgwMzJKY3pBT1NmWUVQZDFCeHlVZFA2UmtNTVplR0FKVFhsTk52UHRV?= =?utf-8?Q?Py5Yp2qmghjVz?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:IA1PR12MB8189.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(366016)(376014)(7053199007);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?eC9WWmtwYmhKNGl3YkxKZXJwMGxXZEVubTZRbWF6YnlTQXl3b3FyZ0hCUEIz?= =?utf-8?B?YlNqSXRsUFNvZ0tDYVk3MXVXZW1SZDhYWHp2UmNCU09IbWJVczVpelZUR01l?= =?utf-8?B?SFRqSnU5bDd3VlEwbWx0MllLSjJtRHlwRkZlS1BIbW5HcUgzbVVjd3NQRkRx?= =?utf-8?B?NEFUd1BlNStWVTdtUWtHS0paTnlyS1BUMVpQM2syaXNWeTdFSWxKdlNRdG8z?= =?utf-8?B?RkxqNjFlQWx6aVdoUUgvQ0hqNjlkMVNVaUxGbUx0RUZHMTl5M3U2ZFNuQlpL?= =?utf-8?B?MVZlZ2dzSko3NjQrU1UyM2ZCMmtmbm0remtZY3lYcWdyckd4WGZIempzeHVP?= =?utf-8?B?bjRIRmhVMWtiNDgrV3crOXVYOVZFZ3l3MjRBUlNZcmw2VERkMFlpOVJrNEZz?= =?utf-8?B?Qms5ZlNOV29RRVZSUWFRWmxaQmNqT01KajhKQnQ0NzFKVVdpVGUveTJTSGdR?= =?utf-8?B?RVlKWEJrOUl1clBhR29MU1NJTHA1Q1ExMWFQNWNMVUIyc2xDTHNFS1dEc2RM?= =?utf-8?B?ay9kMVNwUWYzMkpscXpXRER0c05TRXRKdkRTTWdLblFZQ0FGbW53a2JWOGc1?= =?utf-8?B?M3lJVWdjczVoUXRPbjhjT3A4QnAzOWRGelM0WmV5SWd2c3hGWFFDUGJpUzlG?= =?utf-8?B?enlPTUsyTERQdVhmbDlzYnpaSGhIdmtHQzE0MGtKMFR1cjUzSEgzeS9SWlN6?= =?utf-8?B?TFpzNm1wdy85eFpLTmlqZ3NUZTU0ckVKN1FDUm9sU3JSaEdzeVZQZU9HNytS?= =?utf-8?B?K1loMjFmaThLbmg5YkpqazlLTUd0Qmg0MkU5bGREakhlSkFRNklRRTZNMFg3?= =?utf-8?B?NCtMYWprWHF3Rml1SmxmSDhodk0vblp2dkQ5U2ZINmp5SHc3UHRnK0lja3Jr?= =?utf-8?B?MGtwYnJ3U1U4bmVVcDkrMStGdlFBVlFGbi9VM1JBS3gvSnREWExTd3F6UjQz?= =?utf-8?B?RUJVQTAyWk01a0V6eE9sQzdzemp2em0wZ1NKM3NGREszRTFSb1o2VmJBaDhZ?= =?utf-8?B?U1V6RkYxRzBGaVF0QitlVXVvbWlzSDNBSllRYWtNZGROaUpXa0p1OE8wQ0Zv?= =?utf-8?B?RUdUbEVLSFdaUVZNT1EyTkU4VHl5WmY2TUZuVzNST1ZCVy9qWVFmVVlwNE5v?= =?utf-8?B?MWJ5UFM3d0tFa0hJTmN2NHM2NnNZeGhkSXRvaXNMNWdFdzZ1bi9rQWNPRnox?= =?utf-8?B?NUR0QWd0OXp2OGkyOXBIREVLd0wwQmd0c0JndFZmVXRFYnVoajIrQytxTWVV?= =?utf-8?B?TXM0NWhnVjU4N2N2YVFWWU9rcTZJbkZIUjU2M3RicHUrN2xFMXhoZk1INnBC?= =?utf-8?B?T1luVnRPVFQ2UzVtMjVOVWgvUHlQRS8rNDZ0UHlJa2hpQnZLYXZ5dGJKYW1k?= =?utf-8?B?bGRRKzV3c3gzeCthampkRFFjZno3aGZVRERvWDkvWm1DU2hsVXFQSGo3MXpt?= =?utf-8?B?UUpxVXFieGFMdHlWbm53TEFzUmh1OS9hbFc2bndUMlNZRmt3bjFuSHZzVE01?= =?utf-8?B?R25rTzZxbXpON1V4VFV2WDk2WHExNnNPRXVSc2hraTQvd2haVUtYMGVyOFlG?= =?utf-8?B?c2pyOHpZeWFVdDY0YTg3Q1l2ZzBkWDdQVEFYdHI5ZnZ6eTMwM1V4WFFCRmFM?= =?utf-8?B?SEk3UkFFeEorV0g3RElSeldWc3FFMFdJdFNpaUdSWVpNcmNDVUY2a3VwWTh4?= =?utf-8?B?WE1wTEJGY1ZaRzRYVWRKWjVSRTZvWkNadW9RYVllZ1pqVDZXYWx5MUl6cUFU?= =?utf-8?B?WmcwVXc2aHRNMjh1Y2IxN3d2dDdmNHVyL2RVM1VqRnV0bzQ2ZHBpSXNqaXF3?= =?utf-8?B?UnN1VUtqTzZxcnVHL25mdk5MUHNIVWtvRXhDNzR0SjhlaHV2eUNyUk5xeDJ0?= =?utf-8?B?U0pBZzVVS0JVRGFGZ3J3UTUzVlVOZ1ZTcUhranNPV0ZhU1BNbmdZUnI5OTdh?= =?utf-8?B?RE8xNjlUYk5OVVk2Sks5YTQ3U3ZFNFZnMWQwd0tiV3hsTTY5NW5PZFc5S0Zp?= =?utf-8?B?UmVQeWs2akQ0S2xtd0o0MGNNRmFqNHh0NkdOak9MNEFxbUluTTVqbVJZRFFr?= =?utf-8?B?UjR6OHFCWC9OYVhibVJyMXlGTnJQSm9Oc1dzWHR4cDFrWW5XQ3pRT2s3RXZy?= =?utf-8?Q?admcu6iNXNncS+HK9tk46bs8e?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 2d05e652-7524-4772-09cd-08dd57191264 X-MS-Exchange-CrossTenant-AuthSource: IA1PR12MB8189.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 27 Feb 2025 10:25:35.3359 (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: ovzBGrNwDLEVRdZvhAkqCaG+LyOlJcRC6b15w+ZUIZifxkdUg1Df/veAiD4YFDGT5YlLd7XxH801ejk5J5dySQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4329 On 2/27/2025 2:25 AM, Sean Christopherson wrote: > If KVM rejects an AP Creation event, leave the target vCPU state as-is. > Nothing in the GHCB suggests the hypervisor is *allowed* to muck with vCPU > state on failure, let alone required to do so. Furthermore, kicking only > in the !ON_INIT case leads to divergent behavior, and even the "kick" case > is non-deterministic. > > E.g. if an ON_INIT request fails, the guest can successfully retry if the > fixed AP Creation request is made prior to sending INIT. And if a !ON_INIT > fails, the guest can successfully retry if the fixed AP Creation request is > handled before the target vCPU processes KVM's > KVM_REQ_UPDATE_PROTECTED_GUEST_STATE. > > Fixes: e366f92ea99e ("KVM: SEV: Support SEV-SNP AP Creation NAE event") > Cc: stable@vger.kernel.org > Reviewed-by: Tom Lendacky > Signed-off-by: Sean Christopherson Reviewed-by: Pankaj Gupta > --- > arch/x86/kvm/svm/sev.c | 13 ++++++------- > 1 file changed, 6 insertions(+), 7 deletions(-) > > diff --git a/arch/x86/kvm/svm/sev.c b/arch/x86/kvm/svm/sev.c > index 218738a360ba..9aad0dae3a80 100644 > --- a/arch/x86/kvm/svm/sev.c > +++ b/arch/x86/kvm/svm/sev.c > @@ -3957,16 +3957,12 @@ static int sev_snp_ap_creation(struct vcpu_svm *svm) > > /* > * The target vCPU is valid, so the vCPU will be kicked unless the > - * request is for CREATE_ON_INIT. For any errors at this stage, the > - * kick will place the vCPU in an non-runnable state. > + * request is for CREATE_ON_INIT. > */ > kick = true; > > mutex_lock(&target_svm->sev_es.snp_vmsa_mutex); > > - target_svm->sev_es.snp_vmsa_gpa = INVALID_PAGE; > - target_svm->sev_es.snp_ap_waiting_for_reset = true; > - > /* Interrupt injection mode shouldn't change for AP creation */ > if (request < SVM_VMGEXIT_AP_DESTROY) { > u64 sev_features; > @@ -4012,20 +4008,23 @@ static int sev_snp_ap_creation(struct vcpu_svm *svm) > target_svm->sev_es.snp_vmsa_gpa = svm->vmcb->control.exit_info_2; > break; > case SVM_VMGEXIT_AP_DESTROY: > + target_svm->sev_es.snp_vmsa_gpa = INVALID_PAGE; > break; > default: > vcpu_unimpl(vcpu, "vmgexit: invalid AP creation request [%#x] from guest\n", > request); > ret = -EINVAL; > - break; > + goto out; > } > > -out: > + target_svm->sev_es.snp_ap_waiting_for_reset = true; > + > if (kick) { > kvm_make_request(KVM_REQ_UPDATE_PROTECTED_GUEST_STATE, target_vcpu); > kvm_vcpu_kick(target_vcpu); > } > > +out: > mutex_unlock(&target_svm->sev_es.snp_vmsa_mutex); > > return ret;