From patchwork Wed Dec 6 15:58:21 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: Michael Roth X-Patchwork-Id: 13481968 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 30DD1C4167B for ; Wed, 6 Dec 2023 16:00:25 +0000 (UTC) Received: from localhost ([::1] helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1rAuIx-0002tD-Gz; Wed, 06 Dec 2023 10:59:19 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rAuIv-0002sz-Kr for qemu-devel@nongnu.org; Wed, 06 Dec 2023 10:59:17 -0500 Received: from mail-bn8nam12on20626.outbound.protection.outlook.com ([2a01:111:f400:fe5b::626] helo=NAM12-BN8-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1rAuIl-0004s2-MI for qemu-devel@nongnu.org; Wed, 06 Dec 2023 10:59:17 -0500 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=Grh6tpMUlgfX9Jy7d8sj70YkHCOD6Y3ijp/S9v/bB3wgdA/1+1BG8zhNIg/Jt5klDkFh1IYWFR2iU/A8xKFaZ5ChtGvqtXdrbh5HZ7t2wniW/smyEAko2gGFpurCiMzQ6i4b0QS2ZE0agYqm3mUljhIbhvs/1Gcaa/gZnurLhNnbfg4eigmb901zM0Y0qQxbMvibiTqaeyjVdfyLGxqmtgGtU+Wmj9u+Nssee+BiGBN+SeS5ZdwpMPbn+/cDAbLg95oIM2mLD9spSKAXSVlKeF5ObAjdkgTt1fzMY4M7SkAUjL8jJrMegfq32uRvMAQJziqUY5np78PHZPEdiXn2Iw== 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-AntiSpam-MessageData-ChunkCount:X-MS-Exchange-AntiSpam-MessageData-0:X-MS-Exchange-AntiSpam-MessageData-1; bh=80T7DJv+lZOjy9DTWu2VgFrUpT8q2+yxhOI0LNXDF8E=; b=ocqfp5DVCKSyFPi/MKB46+AOYhUkGK60CAwZDq76DTeINNKgp3Rk+pg9SW/JRYnMcOcElm5ZnjX+GucYNe2vMPFLNa+lzBI3uAU9Ct3cFjxHdT8e6cB5CBQHX9W/P3xHcJM+TPj7Aie0gmqRN8JF+CGyuD+qo/68NmrJAENU98e1VJf0DqNNJyE3Ka2IVRNVWJcu/Fkt0SMZW+sQkcV/oxpGSPlOJujl41KnXEv0t2t7BVlCCFulDAu0ZQMwCz8MTJtk+quY8/2mPiGdI6HIlAZ/u1csBDY/6Tbtd/SUB5x6kaoCtK39oZQG2VbH2tO8whQ3Pk8wjDqEZhlEteG6xg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=nongnu.org smtp.mailfrom=amd.com; dmarc=pass (p=quarantine sp=quarantine pct=100) action=none header.from=amd.com; dkim=none (message not signed); arc=none (0) 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=80T7DJv+lZOjy9DTWu2VgFrUpT8q2+yxhOI0LNXDF8E=; b=i4W4BKzw8ONhtpBu3WT5lHr5MRa7a69MgIyR0jOu5YjPvz4EfzlDjQ42B5VPZqUafQL0tqW2qVeZSv7R22ATuJzJfyxoOlmBFArRmEKHFPIrPVk6jOsKWkt2j+Hu/ALsd/o+0hEZg+12Yw6VAWNtz+gMkMmk2RQZ1ad6+BH4Pjs= Received: from SCZP152CA0010.LAMP152.PROD.OUTLOOK.COM (2603:10d6:300:53::7) by DM3PR12MB9433.namprd12.prod.outlook.com (2603:10b6:0:47::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7068.25; Wed, 6 Dec 2023 15:59:01 +0000 Received: from DS3PEPF000099D7.namprd04.prod.outlook.com (2603:10d6:300:53:cafe::53) by SCZP152CA0010.outlook.office365.com (2603:10d6:300:53::7) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.7046.32 via Frontend Transport; Wed, 6 Dec 2023 15:58:59 +0000 X-MS-Exchange-Authentication-Results: spf=pass (sender IP is 165.204.84.17) smtp.mailfrom=amd.com; dkim=none (message not signed) header.d=none;dmarc=pass action=none header.from=amd.com; Received-SPF: Pass (protection.outlook.com: domain of amd.com designates 165.204.84.17 as permitted sender) receiver=protection.outlook.com; client-ip=165.204.84.17; helo=SATLEXMB04.amd.com; pr=C Received: from SATLEXMB04.amd.com (165.204.84.17) by DS3PEPF000099D7.mail.protection.outlook.com (10.167.17.8) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.7068.20 via Frontend Transport; Wed, 6 Dec 2023 15:58:59 +0000 Received: from localhost (10.180.168.240) by SATLEXMB04.amd.com (10.181.40.145) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.1.2507.34; Wed, 6 Dec 2023 09:58:58 -0600 From: Michael Roth To: CC: Paolo Bonzini , Marcelo Tosatti , Tom Lendacky , Akihiko Odaki , =?utf-8?q?Philippe_Mathieu-Daud?= =?utf-8?q?=C3=A9?= , Lara Lazier , Vitaly Kuznetsov , Maxim Levitsky , Subject: [PATCH v3 for-8.2] i386/sev: Avoid SEV-ES crash due to missing MSR_EFER_LMA bit Date: Wed, 6 Dec 2023 09:58:21 -0600 Message-ID: <20231206155821.1194551-1-michael.roth@amd.com> X-Mailer: git-send-email 2.25.1 MIME-Version: 1.0 X-Originating-IP: [10.180.168.240] X-ClientProxiedBy: SATLEXMB04.amd.com (10.181.40.145) To SATLEXMB04.amd.com (10.181.40.145) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS3PEPF000099D7:EE_|DM3PR12MB9433:EE_ X-MS-Office365-Filtering-Correlation-Id: 79a83fa6-3f35-499c-e9c0-08dbf6744272 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:165.204.84.17; CTRY:US; LANG:en; SCL:1; SRV:; IPV:CAL; SFV:NSPM; H:SATLEXMB04.amd.com; PTR:InfoDomainNonexistent; CAT:NONE; SFS:(13230031)(4636009)(39860400002)(346002)(376002)(396003)(136003)(230922051799003)(186009)(82310400011)(64100799003)(451199024)(1800799012)(36840700001)(40470700004)(46966006)(70586007)(70206006)(36860700001)(356005)(83380400001)(82740400003)(426003)(336012)(16526019)(26005)(2616005)(1076003)(6666004)(478600001)(44832011)(316002)(6916009)(54906003)(86362001)(8676002)(4326008)(8936002)(5660300002)(2906002)(40480700001)(36756003)(41300700001)(47076005)(81166007)(40460700003)(36900700001); DIR:OUT; SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Dec 2023 15:58:59.3742 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 79a83fa6-3f35-499c-e9c0-08dbf6744272 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d; Ip=[165.204.84.17]; Helo=[SATLEXMB04.amd.com] X-MS-Exchange-CrossTenant-AuthSource: DS3PEPF000099D7.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM3PR12MB9433 Received-SPF: softfail client-ip=2a01:111:f400:fe5b::626; envelope-from=Michael.Roth@amd.com; helo=NAM12-BN8-obe.outbound.protection.outlook.com X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.001, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Commit 7191f24c7fcf ("accel/kvm/kvm-all: Handle register access errors") added error checking for KVM_SET_SREGS/KVM_SET_SREGS2. In doing so, it exposed a long-running bug in current KVM support for SEV-ES where the kernel assumes that MSR_EFER_LMA will be set explicitly by the guest kernel, in which case EFER write traps would result in KVM eventually seeing MSR_EFER_LMA get set and recording it in such a way that it would be subsequently visible when accessing it via KVM_GET_SREGS/etc. However, guest kernels currently rely on MSR_EFER_LMA getting set automatically when MSR_EFER_LME is set and paging is enabled via CR0_PG_MASK. As a result, the EFER write traps don't actually expose the MSR_EFER_LMA bit, even though it is set internally, and when QEMU subsequently tries to pass this EFER value back to KVM via KVM_SET_SREGS* it will fail various sanity checks and return -EINVAL, which is now considered fatal due to the aforementioned QEMU commit. This can be addressed by inferring the MSR_EFER_LMA bit being set when paging is enabled and MSR_EFER_LME is set, and synthesizing it to ensure the expected bits are all present in subsequent handling on the host side. Ultimately, this handling will be implemented in the host kernel, but to avoid breaking QEMU's SEV-ES support when using older host kernels, the same handling can be done in QEMU just after fetching the register values via KVM_GET_SREGS*. Implement that here. Cc: Paolo Bonzini Cc: Marcelo Tosatti Cc: Tom Lendacky Cc: Akihiko Odaki Cc: Philippe Mathieu-Daudé Cc: Lara Lazier Cc: Vitaly Kuznetsov Cc: Maxim Levitsky Cc: kvm@vger.kernel.org Fixes: 7191f24c7fcf ("accel/kvm/kvm-all: Handle register access errors") Signed-off-by: Michael Roth Acked-by: Paolo Bonzini --- target/i386/kvm/kvm.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c index 11b8177eff..4ce80555b4 100644 --- a/target/i386/kvm/kvm.c +++ b/target/i386/kvm/kvm.c @@ -3643,6 +3643,10 @@ static int kvm_get_sregs(X86CPU *cpu) env->cr[4] = sregs.cr4; env->efer = sregs.efer; + if (sev_es_enabled() && env->efer & MSR_EFER_LME && + env->cr[0] & CR0_PG_MASK) { + env->efer |= MSR_EFER_LMA; + } /* changes to apic base and cr8/tpr are read back via kvm_arch_post_run */ x86_update_hflags(env); @@ -3682,6 +3686,10 @@ static int kvm_get_sregs2(X86CPU *cpu) env->cr[4] = sregs.cr4; env->efer = sregs.efer; + if (sev_es_enabled() && env->efer & MSR_EFER_LME && + env->cr[0] & CR0_PG_MASK) { + env->efer |= MSR_EFER_LMA; + } env->pdptrs_valid = sregs.flags & KVM_SREGS2_FLAGS_PDPTRS_VALID;