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=-18.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,MSGID_FROM_MTA_HEADER,SPF_HELO_NONE, SPF_PASS,USER_AGENT_GIT autolearn=ham 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 DE7A6C11F68 for ; Wed, 7 Jul 2021 18:16:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C93AF61CCE for ; Wed, 7 Jul 2021 18:16:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232000AbhGGSTV (ORCPT ); Wed, 7 Jul 2021 14:19:21 -0400 Received: from mail-bn8nam12on2057.outbound.protection.outlook.com ([40.107.237.57]:41568 "EHLO NAM12-BN8-obe.outbound.protection.outlook.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S231852AbhGGSTI (ORCPT ); Wed, 7 Jul 2021 14:19:08 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=PMpYYW/7hIy1JvaQr/V18OwzkizWzsGSXtbMoj6JUS3zMSQtieOm+yWeOUaP8an8AQTR/fUeH6JAlxx+MUxiZIhBmiZKLiYYnTVwvPLIysIOwzrh1RxQteifxyAHBNtPdikon95E5cvrvLXKdeq7KlcPZ7IhQM3JTSeQJZKjgkHx9vQHgg5oZnhR78mIZl+Gm6gNKn0Hp9i0pnOhFFKDv+LbgnK3nc8ayATYWrs6T3aEfE3hv2b4Pg0+/40TsQBZ6v3t00huGuBh+Zy0IWId5m0rSUbGBlpCq+UzrPzBKL8hSe1/pZH1zcYYPVRooFhxR/odDnIMx/Xx0YrfoZV5wg== 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=+GAj0n/mh4HxIHmd8pu1nVhyIj/Ean9oCwoFOmBwMJ4=; b=QZDNAd8tCQjcm/zLruYyjQa24/Bo1wwKs3o2Dy1Cwwa9DyyKiGoIYGYnQMfttvQMZIlycv++4fVqGSo+u8B3TpLX283CK39HC4zYGxaPHcpLSj2lZprWyb8staYcpsbqyx5ox2a66aD1t2jz+nwvkKYUjmaIJjUff+iG1Ak/X890MWnUezF07v7S8Lbs+6Xd88ojmJ/G4j3UzUucK5dTMLAWZ1Jax6Y/YNbmWKuqGKyEvyXLvGY1OH//bfB2tr3/JWQrG9mtKxU8GdNf5xF0RoxdKSYrBn5IUYBZfqcf3UL2UmukAUmg7+33DJBk7XuoToSpQJDY7mE71UvsKKcpyQ== 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=+GAj0n/mh4HxIHmd8pu1nVhyIj/Ean9oCwoFOmBwMJ4=; b=5RHnVb78UBKrSMlIKp60JbFxI5m0avGO2ETkiNk6cocqafWzILc9vVMufIKvl2Twzgrc2eBG10HSVmITSCAY1T2B/3JNUCOoDUtPJwSymHXOst7DL5ILTTn7rD80IfuXnqbQU9PNr0UNTA4lAlNL/+v/DvLhgKuhWzpSuFV6pAQ= Authentication-Results: kernel.org; dkim=none (message not signed) header.d=none;kernel.org; dmarc=none action=none header.from=amd.com; Received: from BYAPR12MB2711.namprd12.prod.outlook.com (2603:10b6:a03:63::10) by BY5PR12MB5016.namprd12.prod.outlook.com (2603:10b6:a03:1c5::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4308.20; Wed, 7 Jul 2021 18:16:03 +0000 Received: from BYAPR12MB2711.namprd12.prod.outlook.com ([fe80::40e3:aade:9549:4bed]) by BYAPR12MB2711.namprd12.prod.outlook.com ([fe80::40e3:aade:9549:4bed%7]) with mapi id 15.20.4287.033; Wed, 7 Jul 2021 18:16:02 +0000 From: Brijesh Singh To: x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org, linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org, linux-coco@lists.linux.dev, linux-mm@kvack.org, linux-crypto@vger.kernel.org Cc: Thomas Gleixner , Ingo Molnar , Joerg Roedel , Tom Lendacky , "H. Peter Anvin" , Ard Biesheuvel , Paolo Bonzini , Sean Christopherson , Vitaly Kuznetsov , Wanpeng Li , Jim Mattson , Andy Lutomirski , Dave Hansen , Sergio Lopez , Peter Gonda , Peter Zijlstra , Srinivas Pandruvada , David Rientjes , Dov Murik , Tobin Feldman-Fitzthum , Borislav Petkov , Michael Roth , Vlastimil Babka , tony.luck@intel.com, npmccallum@redhat.com, brijesh.ksingh@gmail.com, Brijesh Singh Subject: [PATCH Part1 RFC v4 14/36] x86/kernel: Validate rom memory before accessing when SEV-SNP is active Date: Wed, 7 Jul 2021 13:14:44 -0500 Message-Id: <20210707181506.30489-15-brijesh.singh@amd.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210707181506.30489-1-brijesh.singh@amd.com> References: <20210707181506.30489-1-brijesh.singh@amd.com> Content-Type: text/plain X-ClientProxiedBy: SA0PR11CA0104.namprd11.prod.outlook.com (2603:10b6:806:d1::19) To BYAPR12MB2711.namprd12.prod.outlook.com (2603:10b6:a03:63::10) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from sbrijesh-desktop.amd.com (165.204.77.1) by SA0PR11CA0104.namprd11.prod.outlook.com (2603:10b6:806:d1::19) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.4308.19 via Frontend Transport; Wed, 7 Jul 2021 18:16:00 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: d6c17605-d6ad-47b6-7608-08d941734783 X-MS-TrafficTypeDiagnostic: BY5PR12MB5016: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:6430; X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BYAPR12MB2711.namprd12.prod.outlook.com;PTR:;CAT:NONE;SFS:(4636009)(346002)(396003)(376002)(366004)(39860400002)(136003)(66556008)(66476007)(186003)(7416002)(52116002)(15650500001)(86362001)(26005)(956004)(8936002)(478600001)(7406005)(7696005)(8676002)(83380400001)(5660300002)(2616005)(38350700002)(38100700002)(44832011)(2906002)(1076003)(54906003)(6666004)(66946007)(316002)(4326008)(36756003)(6486002);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?R/yRKhMEE+J12SNMMPueZRiIJbxEv/x0HAQl1rVMoKtd8zfyC6eCH7W94qnb?= =?us-ascii?Q?RDs7UsBLQ8W5eJCxIxSaA/+ZSjGzfJ8dEsJdP9qVC1byKK29xcGlFwQ9rpp3?= =?us-ascii?Q?Zd4Lrnph131b2+GeQDLU9kvB3OvEUr8inIpKB9Q8pNqRQnZSVUNwJ/LPIsJA?= =?us-ascii?Q?GypzXGUpFwajfdaDkVvz/sD8IVhmtD/BjY4wp+1PG/n+KdP/IQ7xXqtaP6uD?= =?us-ascii?Q?nfEZ4Jth8KupkBS2H9hj3seh8BkAOmYDdyHcJwiUsV4qPq8HtaUko6USv7lI?= =?us-ascii?Q?izds4HzGBoZ2pf+ZXgqdrt1/uYSKtOzU6Pv2Y/DGgvJ5Nl4mWsPdGUJO4kVO?= =?us-ascii?Q?T+DLg6l9lKESKEYlYe6k7xnkxjp1u/wSfIY5c+N5tglnyrLkJzUlPuLxYLm+?= =?us-ascii?Q?viu1PupL3JvFtfgGXyhYmZmx9/AKnP/3m9B9CXAjo3oL/Niqu0s8GgAbqAMg?= =?us-ascii?Q?x+Wu42KIr0WTkK7s7SLFhHU+cmXrMHchgzWi9aX4dRuq205iRc03ZFlHsCAx?= =?us-ascii?Q?VIwWeeaV8r6ItbO3/9a17T/IzSwvKVlEyLaxIKa17I2Hvvejdn1/6kV9tS8J?= =?us-ascii?Q?OholRSMEwSzqyiNL/ZtD0xMXQ9YUpxwgAzwWZQjT2K0U6oKJ+F2M2YPachqz?= =?us-ascii?Q?azjc7vJEbZ7qV7BkMIdSpY9JfxSDeAafHoo8nSyb/ttOWFVww0iXXDVkFGnf?= =?us-ascii?Q?umossHb1HeS3wyYepu9soR19iGhUtT31VVdjJsAuPfbLaHeZrMMBGeVbk/dd?= =?us-ascii?Q?kyxiTwzYEceHIoVS+hmsHutJVRTqDalygD5N3aNmXxk9AJoL5R/16Umfk2+n?= =?us-ascii?Q?yhuRjTNlTbU3poscYacFJ643UN1cPaHfXYbueZRfswe09rLgIJu8jyG3ElnN?= =?us-ascii?Q?+OJcHEwHX1O+W6VNamkEICuClH06fYLTf6uj15UkDDv6C9+uPTZdrNqYrAWF?= =?us-ascii?Q?uwOQExL7F6lPgJlTFdqcVeQ+nQhMufJDPqvKoVUl4KZDOBAHD8ApODjQYfaP?= =?us-ascii?Q?odsf3oBQQ7ggosfE2gh3x2xDkt6R10E7CGiUYAAY8hlOdNvzGRUtqZ6uOtsb?= =?us-ascii?Q?uxLGG4fglqkQCtq5WWPl7UR3y4csuDpHiOVcBSJne56ucen4B/Kgjv3JP716?= =?us-ascii?Q?GOSF3oWfFvSD6H8V/kGrdZ6vIwvRAs0IdzmJKs81z48LIgwvcXx1CaSaEdle?= =?us-ascii?Q?GFb8H8hAWGIzlCKSnz0xpOQjXaxtKD5/nKQsBwpnLA4CKG1JUesVcyXtDm+p?= =?us-ascii?Q?F6eqYCfzENMmO8iBJnK0thoFjqYVIPvFWIO0QMDlC9WsdHraw0wuu5MTj7ay?= =?us-ascii?Q?OLEA+f8B1wAufWYisZbPw6B6?= X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-Network-Message-Id: d6c17605-d6ad-47b6-7608-08d941734783 X-MS-Exchange-CrossTenant-AuthSource: BYAPR12MB2711.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 07 Jul 2021 18:16:02.8167 (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: bTRMRBhlR2P3C9VixrNNYfNEPVCwKtKvR/E+Z1MtOAntDLHJGA34Kfqie/MCJSipK37ub0vfPM877CYW/JsgrQ== X-MS-Exchange-Transport-CrossTenantHeadersStamped: BY5PR12MB5016 Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org The probe_roms() access the memory range (0xc0000 - 0x10000) to probe various ROMs. The memory range is not part of the E820 system RAM range. The memory range is mapped as private (i.e encrypted) in page table. When SEV-SNP is active, all the private memory must be validated before the access. The ROM range was not part of E820 map, so the guest BIOS did not validate it. An access to invalidated memory will cause a VC exception. The guest does not support handling not-validated VC exception yet, so validate the ROM memory regions before it is accessed. Signed-off-by: Brijesh Singh --- arch/x86/kernel/probe_roms.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-) diff --git a/arch/x86/kernel/probe_roms.c b/arch/x86/kernel/probe_roms.c index 9e1def3744f2..9c09df86d167 100644 --- a/arch/x86/kernel/probe_roms.c +++ b/arch/x86/kernel/probe_roms.c @@ -21,6 +21,7 @@ #include #include #include +#include static struct resource system_rom_resource = { .name = "System ROM", @@ -197,11 +198,21 @@ static int __init romchecksum(const unsigned char *rom, unsigned long length) void __init probe_roms(void) { - const unsigned char *rom; unsigned long start, length, upper; + const unsigned char *rom; unsigned char c; int i; + /* + * The ROM memory is not part of the E820 system RAM and is not pre-validated + * by the BIOS. The kernel page table maps the ROM region as encrypted memory, + * the SEV-SNP requires the encrypted memory must be validated before the + * access. Validate the ROM before accessing it. + */ + snp_prep_memory(video_rom_resource.start, + ((system_rom_resource.end + 1) - video_rom_resource.start), + SNP_PAGE_STATE_PRIVATE); + /* video rom */ upper = adapter_rom_resources[0].start; for (start = video_rom_resource.start; start < upper; start += 2048) { -- 2.17.1