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 X-Spam-Level: X-Spam-Status: No, score=-2.2 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,MSGID_FROM_MTA_HEADER, SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A20D8C2BB85 for ; Tue, 14 Apr 2020 20:18:55 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 78360206E9 for ; Tue, 14 Apr 2020 20:18:55 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=amdcloud.onmicrosoft.com header.i=@amdcloud.onmicrosoft.com header.b="vs2SfulZ" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2633013AbgDNUSy (ORCPT ); Tue, 14 Apr 2020 16:18:54 -0400 Received: from mail-dm6nam11on2058.outbound.protection.outlook.com ([40.107.223.58]:17642 "EHLO NAM11-DM6-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2632975AbgDNUSo (ORCPT ); Tue, 14 Apr 2020 16:18:44 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Irjxsq4C6qm1qt7GoNw4KPs35LVaUwYud6D+8DkoDwEPeNJMR94QL9OhS5HiZLWPMOsa7mZfPN7G09O80B3nlWsFz6iMUiQYrgj5bHtWVbEU4TGiX5SZLptax/JPtCgz6Kj1n1SLMU73Pwe3nmqGXf+qltaMTvgYSwI0xotL/pJwtQEsKZ9L6e16tqxcybKRNdBEdvmmbgvziRlVIeCvpE1Hp85NNt78Zrd7gpXollPxn1gpaDxpNzoA3Vj6iYa80xKeRHC9v+ZnxEWGj9MGPNO4RmpEFLVACT+bE4yC0g7nowHY2VUmXmHhDChVMyCJ3QM68MJ8C+yvhiYOCklFAQ== 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-SenderADCheck; bh=6LSJ+GFqYf37nL0QD2n8SQP6nSPYLBlFMkuoebIc7n0=; b=AgX4NmDkdSnw0YRXGmYfK4KzJ5Dr98bJiPgQYF+GZcqagD7Qxw1bsEkQXD/e8C5g4CTbx+ti3kHf/Fc8XzNxx407RDgUspgQbT5Emly5JfdeDOkyFV7O5I8DYjUXxX10+AfoYoWLx8JL/DbpnSKsnp7dzX3AxZMTAziPRceMJsS2gs5SOFbkAhNjnbWy4Fewx1n3+D7yXHJ51F9X5At7Pf36rnIgyFxK0xKbzmuZEZrRzQ+N7NH3aiyTJI5IcaIA/Kp7WCTq0citIe/BLWsAl8OJSH2lQLZ46a9EFn01OvzrUf7K61UPAPfUzyvFe9PVYZYUlyq8zKxKnhw0WW6rUQ== 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=amdcloud.onmicrosoft.com; s=selector2-amdcloud-onmicrosoft-com; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=6LSJ+GFqYf37nL0QD2n8SQP6nSPYLBlFMkuoebIc7n0=; b=vs2SfulZw6HKxypJ7YSm8qN5Gj8mwS24RuNuN2G83JI09XUv8o7IU535AJs23x2mt1d2w4qoa0P35HUBu7Roah022W3gyIni1nIRbqBcfkgyeVUqi0ijk5mPt7ZTuWwenZH/l3YV9Wj4y/mIq/Q4AoHn2m1XZfcUcj5qDulSdB0= Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=Thomas.Lendacky@amd.com; Received: from DM6PR12MB3163.namprd12.prod.outlook.com (2603:10b6:5:15e::26) by DM6PR12MB3369.namprd12.prod.outlook.com (2603:10b6:5:117::16) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2900.26; Tue, 14 Apr 2020 20:18:40 +0000 Received: from DM6PR12MB3163.namprd12.prod.outlook.com ([fe80::f0f9:a88f:f840:2733]) by DM6PR12MB3163.namprd12.prod.outlook.com ([fe80::f0f9:a88f:f840:2733%7]) with mapi id 15.20.2900.028; Tue, 14 Apr 2020 20:18:40 +0000 Subject: Re: [PATCH 40/70] x86/sev-es: Setup per-cpu GHCBs for the runtime handler From: Tom Lendacky To: Dave Hansen , Mike Stunes , Joerg Roedel Cc: "x86@kernel.org" , "hpa@zytor.com" , Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , Joerg Roedel References: <20200319091407.1481-1-joro@8bytes.org> <20200319091407.1481-41-joro@8bytes.org> <09757a84-1d81-74d5-c425-cff241f02ab9@amd.com> <27da7cf5-5ff4-a10c-a506-de77aeff8dd6@amd.com> Message-ID: Date: Tue, 14 Apr 2020 15:18:36 -0500 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:68.0) Gecko/20100101 Thunderbird/68.4.1 In-Reply-To: <27da7cf5-5ff4-a10c-a506-de77aeff8dd6@amd.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: SN6PR04CA0096.namprd04.prod.outlook.com (2603:10b6:805:f2::37) To DM6PR12MB3163.namprd12.prod.outlook.com (2603:10b6:5:15e::26) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from office-linux.texastahm.com (67.79.209.213) by SN6PR04CA0096.namprd04.prod.outlook.com (2603:10b6:805:f2::37) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2900.18 via Frontend Transport; Tue, 14 Apr 2020 20:18:38 +0000 X-Originating-IP: [67.79.209.213] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-HT: Tenant X-MS-Office365-Filtering-Correlation-Id: f3fbe02e-aa70-46df-e1c0-08d7e0b105a2 X-MS-TrafficTypeDiagnostic: DM6PR12MB3369: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8882; X-Forefront-PRVS: 0373D94D15 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DM6PR12MB3163.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFTY:;SFS:(10009020)(4636009)(136003)(366004)(346002)(376002)(396003)(39860400002)(31696002)(8936002)(2616005)(81156014)(31686004)(8676002)(6486002)(478600001)(186003)(86362001)(16526019)(26005)(4744005)(7416002)(6512007)(54906003)(53546011)(956004)(6506007)(66476007)(316002)(5660300002)(2906002)(52116002)(36756003)(4326008)(66946007)(110136005)(66556008);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: dJLZ4sUAadPewVYoEvDRLakPJxqb8Cg44TncB67WKhuj1j/UdJUkgacuTWLwvKKacrq5xKWT3jNZKBedqFbAW/97YfqHiG3kGrIdV4uXvJdohbpwGxSrXd8vzdTzsDrVb+jPI8f0as7mL1Mn3/MRIzNm57Ke3KXPV51G9GFcUdii0yMLgivkfjYbGZux5RgrwK7VUITDu6bAc4r+UJf5SJkc1vLQoNbDff5a+lIVViLxfp13OHIJ7eoruu6MGn7y7mYDUgQB2v/R9WVhv2pgscpZrCeGbU40sKIH/7qg7TZ10ZjFhEZOcNhMRBhbMkvitKusaI7bZJHWliIaJnH6/6NJ8e0OcXB8B7+FqyebYWQMX3G9pQqSaBw/aDaFRmRyNxs0bY8MpoBaSpkGVay0dYNUn1/VTrSs+51MRgvRyt+P/am9a2ijD1tljIWxNpQr X-MS-Exchange-AntiSpam-MessageData: SVinSn76/xQxl5el555qMLqsPAqxfletWLwb1f5+JTxrmWYn7UIooyUEAl04kduqOKI+bIEWfbap9LAAStg4DNzLf6wYboVUuiavoMN16stLqZUWTWcW+PQH69s/Svx2tLRzOlGOx3snlWp6jfnkVQ== X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: f3fbe02e-aa70-46df-e1c0-08d7e0b105a2 X-MS-Exchange-CrossTenant-OriginalArrivalTime: 14 Apr 2020 20:18:40.6597 (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: NexKPymXl9HUzj8c12xbH7RcY851eEovXyME3a22AVXyGrg/sRzLBf6t4fzjDz/fmzQS7vnu4YMMlDqWo52q2Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB3369 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 4/14/20 3:16 PM, Tom Lendacky wrote: > > > On 4/14/20 3:12 PM, Dave Hansen wrote: >> On 4/14/20 1:04 PM, Tom Lendacky wrote: >>>> set_memory_decrypted needs to check the return value. I see it >>>> consistently return ENOMEM. I've traced that back to split_large_page >>>> in arch/x86/mm/pat/set_memory.c. >>> >>> At that point the guest won't be able to communicate with the >>> hypervisor, too. Maybe we should BUG() here to terminate further >>> processing? >> >> Escalating an -ENOMEM into a crashed kernel seems a bit extreme. >> Granted, the guest may be in an unrecoverable state, but the host >> doesn't need to be too. >> > > The host wouldn't be. This only happens in a guest, so it would be just > causing the guest kernel to panic early in the boot. And I should add that it would only impact an SEV-ES guest. Thanks, Tom > > Thanks, > Tom > From mboxrd@z Thu Jan 1 00:00:00 1970 From: Tom Lendacky Subject: Re: [PATCH 40/70] x86/sev-es: Setup per-cpu GHCBs for the runtime handler Date: Tue, 14 Apr 2020 15:18:36 -0500 Message-ID: References: <20200319091407.1481-1-joro@8bytes.org> <20200319091407.1481-41-joro@8bytes.org> <09757a84-1d81-74d5-c425-cff241f02ab9@amd.com> <27da7cf5-5ff4-a10c-a506-de77aeff8dd6@amd.com> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8; format=flowed Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <27da7cf5-5ff4-a10c-a506-de77aeff8dd6@amd.com> Content-Language: en-US Sender: kvm-owner@vger.kernel.org To: Dave Hansen , Mike Stunes , Joerg Roedel Cc: "x86@kernel.org" , "hpa@zytor.com" , Andy Lutomirski , Dave Hansen , Peter Zijlstra , Thomas Hellstrom , Jiri Slaby , Dan Williams , Juergen Gross , Kees Cook , "linux-kernel@vger.kernel.org" , "kvm@vger.kernel.org" , "virtualization@lists.linux-foundation.org" , Joerg Roedel List-Id: virtualization@lists.linuxfoundation.org On 4/14/20 3:16 PM, Tom Lendacky wrote: > > > On 4/14/20 3:12 PM, Dave Hansen wrote: >> On 4/14/20 1:04 PM, Tom Lendacky wrote: >>>> set_memory_decrypted needs to check the return value. I see it >>>> consistently return ENOMEM. I've traced that back to split_large_page >>>> in arch/x86/mm/pat/set_memory.c. >>> >>> At that point the guest won't be able to communicate with the >>> hypervisor, too. Maybe we should BUG() here to terminate further >>> processing? >> >> Escalating an -ENOMEM into a crashed kernel seems a bit extreme. >> Granted, the guest may be in an unrecoverable state, but the host >> doesn't need to be too. >> > > The host wouldn't be. This only happens in a guest, so it would be just > causing the guest kernel to panic early in the boot. And I should add that it would only impact an SEV-ES guest. Thanks, Tom > > Thanks, > Tom >