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To: Ashish Kalra References: <0caf809845d2fdb1a1ec17955826df9777f502fb.1585548051.git.ashish.kalra@amd.com> <95d6d6e3-21d5-17c3-a0a5-dc0bac6d87ca@amd.com> <20200330164525.GB21601@ashkalra_ubuntu_server> From: Brijesh Singh Message-ID: <3dccbcc9-c9b9-c98a-357a-dafde04984f6@amd.com> Date: Tue, 31 Mar 2020 09:26:26 -0500 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.14; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 In-Reply-To: <20200330164525.GB21601@ashkalra_ubuntu_server> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Content-Language: en-US X-ClientProxiedBy: DM5PR07CA0098.namprd07.prod.outlook.com (2603:10b6:4:ae::27) To SA0PR12MB4400.namprd12.prod.outlook.com (2603:10b6:806:95::13) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from Brijeshs-MacBook-Pro.local (165.204.77.11) by DM5PR07CA0098.namprd07.prod.outlook.com (2603:10b6:4:ae::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2856.20 via Frontend Transport; Tue, 31 Mar 2020 14:26:28 +0000 X-Originating-IP: [165.204.77.11] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: 6ff1b7a2-3727-4768-07d9-08d7d57f81bb X-MS-TrafficTypeDiagnostic: SA0PR12MB4480:|SA0PR12MB4480: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:3631; X-Forefront-PRVS: 0359162B6D X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:SA0PR12MB4400.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(10009020)(4636009)(39860400002)(366004)(346002)(376002)(396003)(136003)(2906002)(44832011)(316002)(31686004)(37006003)(956004)(7416002)(478600001)(8936002)(6512007)(81166006)(6636002)(81156014)(2616005)(52116002)(16526019)(26005)(4326008)(6862004)(5660300002)(6486002)(186003)(8676002)(31696002)(66946007)(66476007)(86362001)(53546011)(66556008)(36756003)(6506007);DIR:OUT;SFP:1101; Received-SPF: None (protection.outlook.com: amd.com does not designate permitted sender hosts) X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 1KxUIF9OuaYegSXPyXakDt3R+OkooZ7dzNCchx1UtXbuxKaK+jkijqUArZF3ZdbC22bls1Hcq33N2NBokQ63g1YQ7K7xEDmht9cx5Rw23KpZeTW+Wqmq76YN2RNd8eaDhj0m8K0kkMd5Uf7cSsRCy+sJPbSIckxjrrPVwG4zXmwZmhBygYu4XTpGjJoYxiyHN20n30nyhU3YnrcVYdzq/cvhKHGupP5h8kf3OwAgyRugJqKwO8qfDlY7iLnmiQXYUwUH2weL7fnSB/rFkjX3eZOfWjTqQ4xEVwyhqAehnnUmB3ynsMYcCHB9s9tMWZbvyLhP7u8I2uUANvH+YPAjZcxiY20eeNlNt0p9lIf+9vxSuAgq5whmUbgJxNepJfWqj/1AOK5IQs6sYreawW0Umq2V2qf+8VvYF03OirLQkm622K/NAVPSBMFN80Zhqcty X-MS-Exchange-AntiSpam-MessageData: EFjK6Gvy95RCZ0jjMmTCgedDaS1S35wr9lgdKSxG/K02GtBZM4QLHigPkR2ACWjWzJM37ystY/vIluvH3H1+2v4qMarIAFzVGYjZrbO/BKRW0GD9FhD9/lkiPVfOo0Z659MxdZObEIjCOdw5HWYBeQ== X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6ff1b7a2-3727-4768-07d9-08d7d57f81bb X-MS-Exchange-CrossTenant-OriginalArrivalTime: 31 Mar 2020 14:26:31.3441 (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: kDvq1UyHEIhjeq10C5ruyTRm5FycrBEh6EO+XXV/96JEXImvMXWrL4DCnr2r/efqcw39eMcilsrBGO7EUoNcuQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA0PR12MB4480 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 3/30/20 11:45 AM, Ashish Kalra wrote: > Hello Brijesh, > > On Mon, Mar 30, 2020 at 11:00:14AM -0500, Brijesh Singh wrote: >> On 3/30/20 1:23 AM, Ashish Kalra wrote: >>> From: Ashish Kalra >>> >>> Reset the host's page encryption bitmap related to kernel >>> specific page encryption status settings before we load a >>> new kernel by kexec. We cannot reset the complete >>> page encryption bitmap here as we need to retain the >>> UEFI/OVMF firmware specific settings. >>> >>> Signed-off-by: Ashish Kalra >>> --- >>> arch/x86/kernel/kvm.c | 28 ++++++++++++++++++++++++++++ >>> 1 file changed, 28 insertions(+) >>> >>> diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c >>> index 8fcee0b45231..ba6cce3c84af 100644 >>> --- a/arch/x86/kernel/kvm.c >>> +++ b/arch/x86/kernel/kvm.c >>> @@ -34,6 +34,7 @@ >>> #include >>> #include >>> #include >>> +#include >>> >>> static int kvmapf = 1; >>> >>> @@ -357,6 +358,33 @@ static void kvm_pv_guest_cpu_reboot(void *unused) >>> */ >>> if (kvm_para_has_feature(KVM_FEATURE_PV_EOI)) >>> wrmsrl(MSR_KVM_PV_EOI_EN, 0); >>> + /* >>> + * Reset the host's page encryption bitmap related to kernel >>> + * specific page encryption status settings before we load a >>> + * new kernel by kexec. NOTE: We cannot reset the complete >>> + * page encryption bitmap here as we need to retain the >>> + * UEFI/OVMF firmware specific settings. >>> + */ >>> + if (kvm_para_has_feature(KVM_FEATURE_SEV_LIVE_MIGRATION) && >>> + (smp_processor_id() == 0)) { >> >> In patch 13/14, the KVM_FEATURE_SEV_LIVE_MIGRATION is set >> unconditionally and because of that now the below code will be executed >> on non-SEV guest. IMO, this feature must be cleared for non-SEV guest to >> avoid making unnecessary hypercall's. >> >> > I will additionally add a sev_active() check here to ensure that we don't make the unnecassary hypercalls on non-SEV guests. IMO, instead of using the sev_active() we should make sure that the feature is not enabled when SEV is not active. >>> + unsigned long nr_pages; >>> + int i; >>> + >>> + for (i = 0; i < e820_table->nr_entries; i++) { >>> + struct e820_entry *entry = &e820_table->entries[i]; >>> + unsigned long start_pfn, end_pfn; >>> + >>> + if (entry->type != E820_TYPE_RAM) >>> + continue; >>> + >>> + start_pfn = entry->addr >> PAGE_SHIFT; >>> + end_pfn = (entry->addr + entry->size) >> PAGE_SHIFT; >>> + nr_pages = DIV_ROUND_UP(entry->size, PAGE_SIZE); >>> + >>> + kvm_sev_hypercall3(KVM_HC_PAGE_ENC_STATUS, >>> + entry->addr, nr_pages, 1); >>> + } >>> + } >>> kvm_pv_disable_apf(); >>> kvm_disable_steal_time(); >>> } > Thanks, > Ashish