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Peter Anvin" , mgross@linux.intel.com, Vitaly Kuznetsov , kim.phillips@amd.com, wei.huang2@amd.com References: <160738054169.28590.5171339079028237631.stgit@bmoger-ubuntu> <160738067105.28590.10158084163761735153.stgit@bmoger-ubuntu> From: Babu Moger Message-ID: <2e929c9a-9da9-e7da-9fd4-8e0ea2163a19@amd.com> Date: Wed, 9 Dec 2020 16:39:31 -0600 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.10.0 In-Reply-To: Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit X-Originating-IP: [165.204.77.1] X-ClientProxiedBy: CH2PR07CA0027.namprd07.prod.outlook.com (2603:10b6:610:20::40) To SN1PR12MB2560.namprd12.prod.outlook.com (2603:10b6:802:26::19) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [10.236.31.136] (165.204.77.1) by CH2PR07CA0027.namprd07.prod.outlook.com (2603:10b6:610:20::40) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3654.12 via Frontend Transport; Wed, 9 Dec 2020 22:39:33 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: 8575c9d5-007e-4061-eac2-08d89c934e12 X-MS-TrafficTypeDiagnostic: SN1PR12MB2591: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:4502; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: cEWEnFXotWmvZYadkauTxxI522IJ6Svy0moxToL1cZBp2Oxn1FpcDVsTaKzzxGwg+PBTIM0ilw8AE6vFrt0brKRyrSFDeADyR9ip9xnh66ogAGF9TNqypE9rAUbNW4iF51bWPwaqJkWpMCar7nuHPPPYYz/nOXSF2t9W0cAQWZZ1v8pb4z7BFMWe1K8QYboK5Fu79PJYUeafrsyLfo2DwU2rXdb2yNr1krFFZz9F2N8kCrZ8SsO63bJYzD8GePKwnpr06q72GwBOJh8lDo7HgeS1E0/UPldUYSafF2SDbMGIXvgNbZgJZJtAxbXSSCc2N96cmU4uoywNppKKf4NnLTpwdbB3VG/OlMvQDWXVobDz2dRya+4Z82JrfZ9EwGsoyUKutxLkbV1ZOoRDaU8PBYbczHuVxB6ElB3B3f//HRr798qNUIL6Vy8hXa7Omo5R X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SN1PR12MB2560.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(136003)(346002)(376002)(366004)(8936002)(16526019)(26005)(52116002)(4326008)(53546011)(7416002)(34490700003)(2906002)(186003)(8676002)(54906003)(66556008)(16576012)(66476007)(44832011)(956004)(6916009)(66946007)(5660300002)(2616005)(31696002)(86362001)(6486002)(508600001)(31686004)(36756003)(43740500002)(45980500001);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData: =?utf-8?B?dlovcnBYY1kvblFHZ2ZuT2pwNHVOM1BSU3g4cmRjaWk2MEt2NzhQRmwzVEMz?= =?utf-8?B?NHpmN2ZWM2YyT1RJQ3dROVdyVk11eDZMME1oZkN6L3lKZUFuMVl4OHVtQVN1?= =?utf-8?B?bXo3eTZ3TTVCZ1JEYTVsbXYrSGszTHcvT0hxQTNhQTZnalAvek9YeWFuaGth?= =?utf-8?B?TW9CWDBCQkg4M3Ivd2ptcjBadXBQMFRiQUdLRjBKQUNCNVFuVnFhMGR1dis1?= =?utf-8?B?TXIwTVNaU2RvZmlwZXdOUlhpQzhRZDYwNTYvekl3Rm5haEFzRVFxdThlVkhU?= =?utf-8?B?Mmkxak50N3RNNGtVK01WTmtGMGxycHljbmRBUTN0bmRHWFZLdzVrWGQxenY5?= =?utf-8?B?M09TRnVKclBQZHBJR1h6UjVMVHY1UGtIWWVkSitqeDdFUXZZd1diSkpPREFZ?= =?utf-8?B?VVdpKzFyMHpGWjIyaXZaOUNVRTlnUm55NTNGT255MHNLRDdyV2N0L3JzTU1j?= =?utf-8?B?VmVEYkcva3FxcTBrUFNoYzFwTThvRmx2YnJBWU9xYWZHRWVmUld6OWxuTTBR?= =?utf-8?B?SkFiakZvRDQvTHdvbE9SWW5nb04vK3NaQkNXWi9GT3M3NUlCSUZGYVg4ZFNU?= =?utf-8?B?dzRwL2IzWkhxWjhsSUZWbFk3VTJubWd5Q2RqWjduNExteDFMYngyMnJmRXZa?= =?utf-8?B?bEZYa1Z3ZnMyR2lKcEtHbitRajY2TC83cDhFU2M0c0grOWh0VktTZFREbEly?= =?utf-8?B?QUROdTg1Qlh6NXlhYWpPZiswRUlKZ28yTE5uOXhtQ1l0K2FobThPVUs3SklN?= =?utf-8?B?MlRxYzQ2bVhWcEVQZEJhR0MyODFQNWQxSlhoSG9jcHJzankxRytnbHpjQk1S?= =?utf-8?B?RjZWejJOTWJBM3lxQ1daV1JXUGZJTVlmV040a0prTDJ3b205TFNMZE8rSHBr?= =?utf-8?B?cERYMmVZc2IzY05YQmdkaEJrK2tjek9YeXpEcXdVWmVoK2lIVC9EUEFUZ0xq?= =?utf-8?B?amllWXRNNGhaR0NwdHIyUkJFRzdIMWg2N0c4MDgvU1BkYWt0MHFaSklHWERn?= =?utf-8?B?WXc0QUFQV0N1L2xKT3NPZ2RoSzFUOE5HRVVXcHlvdTNTVjZ5ZzZGS2djdjlN?= =?utf-8?B?ZnJibFoyZE4zRHJOUkFLbDdEQXFPVmkyVnFOU2xscHBLU1NqaXBMclhlVmxa?= =?utf-8?B?ZGZCcUhMMnorb1BYNGpUU2RJSmphazIwWEx1OHJOd0tEWDRNbStYbHNwMU9H?= =?utf-8?B?MkFzTFpWQ2JaQ0NCS3hRMmNjM0NwVnZiQjZMVGxOenRmQVFUNFpHSnE1REZD?= =?utf-8?B?Ym1OWlpyaHdHRHY4YUp4V29wN09sU2JPd1FTSG9UYzNKZkpSZ2tadWtPZGNa?= =?utf-8?Q?mTIgwFvWCcffQCKGImWfpcH5eT5oorwACA?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-AuthSource: SN1PR12MB2560.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Dec 2020 22:39:35.5204 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-Network-Message-Id: 8575c9d5-007e-4061-eac2-08d89c934e12 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: HIuAJg2NMPtcFCkREflAsZAl2yJWpOeylXDd5adnR4a1CtedH0dbjrAmJARFBq+o X-MS-Exchange-Transport-CrossTenantHeadersStamped: SN1PR12MB2591 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 12/7/20 5:22 PM, Jim Mattson wrote: > On Mon, Dec 7, 2020 at 2:38 PM Babu Moger wrote: >> >> Newer AMD processors have a feature to virtualize the use of the SPEC_CTRL >> MSR. This feature is identified via CPUID 0x8000000A_EDX[20]. When present, >> the SPEC_CTRL MSR is automatically virtualized and no longer requires >> hypervisor intervention. >> >> Signed-off-by: Babu Moger >> --- >> arch/x86/include/asm/cpufeatures.h | 1 + >> 1 file changed, 1 insertion(+) >> >> diff --git a/arch/x86/include/asm/cpufeatures.h b/arch/x86/include/asm/cpufeatures.h >> index dad350d42ecf..d649ac5ed7c7 100644 >> --- a/arch/x86/include/asm/cpufeatures.h >> +++ b/arch/x86/include/asm/cpufeatures.h >> @@ -335,6 +335,7 @@ >> #define X86_FEATURE_AVIC (15*32+13) /* Virtual Interrupt Controller */ >> #define X86_FEATURE_V_VMSAVE_VMLOAD (15*32+15) /* Virtual VMSAVE VMLOAD */ >> #define X86_FEATURE_VGIF (15*32+16) /* Virtual GIF */ >> +#define X86_FEATURE_V_SPEC_CTRL (15*32+20) /* Virtual SPEC_CTRL */ > > Shouldn't this bit be reported by KVM_GET_SUPPORTED_CPUID when it's > enumerated on the host? Jim, I am not sure if this needs to be reported by KVM_GET_SUPPORTED_CPUID. I dont see V_VMSAVE_VMLOAD or VGIF being reported via KVM_GET_SUPPORTED_CPUID. Do you see the need for that? >> /* Intel-defined CPU features, CPUID level 0x00000007:0 (ECX), word 16 */ >> #define X86_FEATURE_AVX512VBMI (16*32+ 1) /* AVX512 Vector Bit Manipulation instructions*/ >>