From nobody Sun Feb 8 14:13:04 2026 Received: from NAM02-DM3-obe.outbound.protection.outlook.com (mail-dm3nam02on2049.outbound.protection.outlook.com [40.107.95.49]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 2B844230BFA for ; Mon, 10 Mar 2025 16:40:41 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.95.49 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741624843; cv=fail; b=UWepbkgGEs0F6BMl9sGh32shE+FjoTqVYBtzu7lV6DmOvy4bx/4BYfVNlan8JFhgirmkmVRXtr1i4QgD8wpM3aGNnBBZhL3ObYofElDX8XB8lB3xCMldqvr1DmoBnqXZ85DBBqwvHHZWNxK81Ceqlxb4gnXWvvBYu1+AfkzEpXQ= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741624843; c=relaxed/simple; bh=DF6MZbZJpXCPECopF9eNLvNxgjJUadmOofM1ZNLxQU8=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=qYTCqcj1ugVB31kWcQ9RB7RejGspw6ymxGGNZL3UwAUESMQpsrQDnahX+FkNUQIK9JNCFd8mHR4RyLGHnPz9c8GCocZVi5mgQuaaeRfdOL2oXoT1PdKJpdpzCEVw+its7prNLFxP5+Iz7gX+8vZ//D7uoGxDZb/Cud7d5MXyIoM= ARC-Authentication-Results: i=2; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com; spf=fail smtp.mailfrom=amd.com; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b=j52C9zVU; arc=fail smtp.client-ip=40.107.95.49 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=amd.com Authentication-Results: smtp.subspace.kernel.org; spf=fail smtp.mailfrom=amd.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=amd.com header.i=@amd.com header.b="j52C9zVU" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=fNrwr5Md0ueDFqgc33Vpnc7uAqllI0LWVkYqbWvG4k/g4lxxzSrzxdTwvle5yjebCOFkwXU6JgfYpGgySAxAdSK7/xy6DMI5yblyaXTeTv/dvEEOy9aqzV34WzOGadh/p/hZ67TCFiBvzEPHEeYUSrAgO66cPBezvMOoTRavmU+w/OLM+TCQgwCQBBMZMCZmvBnedBv/e/pnkx/hem7rEWJb1sFiKoZYO1TfcTIUChmN5+LeeXx8QmT9SMjg42b6GVSCGonX9F1WwNEosp8MTPHMWpsD1Ejy9HIISaHDHO6mOevaWHYEVXNYUJ6p7cr7Q0hFphTgT1qxGzhUrrd12A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector10001; 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=JV6/HIURgDQZVllu3rS46Vt4KguJ+iml0Cn2OfCIHEc=; b=TNEQ5nZgSPAXXOLfBvF+ejkE/ZjnoembPvu7gp6kMDBojz4Y19XZIEnJ81g1jG7RLPQPRQpreoDebguSqjWaqD2v1r70VAwqC7QbNx//7L93AL+ITf7gDTbIyiZkz6HspSYbQv/epdB/HbbjPrKEN0WIGnUt6plRkacvKzoSBSUko9XZy+IuQeMWitEw+sJ6CS9SrcIWH+mf30Wrp59WdiVSa43MGXhZJWwg0q2nuf1git5s9ReQtgSUFq8qpv1Xt7enxf3unaB0AgmN6u9eK9UTut7WAEI0K7g+yV92YWbmJqhFvTN/mjX0falAT++50U15GOTI0MgW3CMlmaMVjg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass (sender ip is 165.204.84.17) smtp.rcpttodomain=linutronix.de 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=JV6/HIURgDQZVllu3rS46Vt4KguJ+iml0Cn2OfCIHEc=; b=j52C9zVUtGecMp/XxLd1zOcLP8p0FosYitJqZNweldD4DoAzGNZscwLyhFs/7F6s845/D7/PEIgLKNDOY+nfPTOVWfcUOdOvG5AT/ZpvI9rYmGSavE0+EdwcQdQwFHWBPVtSF/k0FnOHhh6KGY6DJJCfRBIqOHKaRNlYhHuhVzI= Received: from BN9PR03CA0085.namprd03.prod.outlook.com (2603:10b6:408:fc::30) by SA1PR12MB8642.namprd12.prod.outlook.com (2603:10b6:806:383::11) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8511.26; Mon, 10 Mar 2025 16:40:38 +0000 Received: from BL6PEPF00022574.namprd02.prod.outlook.com (2603:10b6:408:fc:cafe::d2) by BN9PR03CA0085.outlook.office365.com (2603:10b6:408:fc::30) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.8511.26 via Frontend Transport; Mon, 10 Mar 2025 16:40:38 +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 BL6PEPF00022574.mail.protection.outlook.com (10.167.249.42) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256) id 15.20.8534.20 via Frontend Transport; Mon, 10 Mar 2025 16:40:38 +0000 Received: from tiny.amd.com (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 15.1.2507.39; Mon, 10 Mar 2025 11:40:36 -0500 From: David Kaplan To: Thomas Gleixner , Borislav Petkov , Peter Zijlstra , Josh Poimboeuf , Pawan Gupta , Ingo Molnar , Dave Hansen , , "H . Peter Anvin" CC: , Brendan Jackman , Derek Manwaring Subject: [PATCH v4 04/36] x86/bugs: Restructure rfds mitigation Date: Mon, 10 Mar 2025 11:39:51 -0500 Message-ID: <20250310164023.779191-5-david.kaplan@amd.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20250310164023.779191-1-david.kaplan@amd.com> References: <20250310164023.779191-1-david.kaplan@amd.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: BL6PEPF00022574:EE_|SA1PR12MB8642:EE_ X-MS-Office365-Filtering-Correlation-Id: 325df83b-859d-4b7b-cfe4-08dd5ff249c1 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|36860700013|1800799024|7416014|376014|82310400026; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?L8+VWEj610gyjRIzogUThfSdZhv7p8ClXfPbMnSpB6U1cC74B/YDY+zCBIry?= =?us-ascii?Q?ocO5dvifOcoxum/KzrfuG0IwzanI/VyucP7CeXfJOSNlkMPqiRSrDBgUeLfM?= =?us-ascii?Q?7i9jvWv1OzLO3bpb1YBCukTxgbDIqqmwjceUYiKne9uWwW47DoRcpfQ1RGdM?= =?us-ascii?Q?wih/t6G0OxhQ+xgjHAY7ZbNgTIOiOHAEhSvaWnIxdJNPWpW7t3VLK0+pZDHi?= =?us-ascii?Q?F1UU1E+cEHQdlszqJI8rScE19TelgmRlM1ksqWB2UwHQ8NoYprIhejXu3z/K?= =?us-ascii?Q?c0CWZO2+oIYaBNovl5sBzql1ewcuykbqVR2LXsX6AVb/2K/3M37Kjc5/GYoD?= =?us-ascii?Q?Rn9nyuoYJtWIfvguvS4ZEFfobbbE8cNdsC1lTHpsXMPD9itr2Ca/og49gcFH?= =?us-ascii?Q?izLcTjJjCHPL1pPqug/QAluYguKJAGr4loDHo4zY6/GpqTxB9QSlZdzO8QA1?= =?us-ascii?Q?vDx0B2lPuBIF8E/1dbUf1xH/1B/bsddQuqYvkkuad0iAcOad+gx3aOERVVrm?= =?us-ascii?Q?lPxDhf4Qoy4O237AzxcyDiIvun0lQ4rbCn8NR3igdFGX15+5Tkb2JOCFLKzz?= =?us-ascii?Q?8aNoh4oEgUbr6muLCHKYZxAnSeh3XfK00m1M/KvydbarZw6604CzC4HuVfIW?= =?us-ascii?Q?HOVuVjSA/2imAvhcqsFdqg7CyGSAED/0fOb00y3VpRjNxPokHeFczkwHOKxl?= =?us-ascii?Q?FqnkC7HXj8TJxlhKpIAHeV2S8c4YCuuo1l55d8jWtj2w/86bHQBRNza1F3zL?= =?us-ascii?Q?5R9rjkqGF6A4QDgJZ4SEJNTVlsvvdFldk+AtIHTL0sp5qZO7t2++AYEYqJRe?= =?us-ascii?Q?IF3qUkiFTCBWktch7vpowX3DIG76ecUA4DzNW+xg0EhB2M7Jz+WLLwJOR/9z?= =?us-ascii?Q?MooMh0rvCgxkAcLG9i5JuGKKT24f7QBfp6Tptv0H9TNJJH/dmiai0lGawQSm?= =?us-ascii?Q?YmUZ5l1Gl4Ps4rcc9ASaJ362zoWObU8iYi0791+eUAxAmB3KnBhi4y2qRlwU?= =?us-ascii?Q?dxeCXvbJ4m9xQMu90oo/NCm+8yD4boTnoTiuH2p2zeeaNppR+hV4tTVsP9FR?= =?us-ascii?Q?/Q8YAf1G67rGKlm79yjM08/bs5a90UOUsIBg+OXk6fw9snTWXOaayD0K4Qcg?= =?us-ascii?Q?+qXqqSlWoAmjbjd1FX5rfQBZQRnzBfBz/KmbZPOUszlf20LKAZe/LJurWAzG?= =?us-ascii?Q?VN4CXQ4BTyJDNX7K1xd2Gur5v9aTY1h5JAWxtfT4FxpHXsGNqGKOSALKzODJ?= =?us-ascii?Q?MnJBE8mRiRSh9PzsmXBQIWnBJggByYOK8sj7/m+dorccc7a4t8UK7x23/KpX?= =?us-ascii?Q?8HjaHTbc3pbVkVBxOEoNA2Skt8q79zDzWPqHIBrKzo72ltCFZes/cdQT4Vro?= =?us-ascii?Q?oHvvE3d4x2siqeN9mZ/XEqcKiXt0PdKsC6KIrAsMoqMgfpc/47hA2KzjIb/7?= =?us-ascii?Q?DeL7UOmVA6GEvHb+4+90HirkSvIMBE4YiyY8aGs3Dd5VbOgaoguT080ri/S+?= =?us-ascii?Q?pOs15f4+0riZ/1Y=3D?= 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:(13230040)(36860700013)(1800799024)(7416014)(376014)(82310400026);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Mar 2025 16:40:38.0172 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 325df83b-859d-4b7b-cfe4-08dd5ff249c1 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: BL6PEPF00022574.namprd02.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA1PR12MB8642 Content-Type: text/plain; charset="utf-8" Restructure rfds mitigation to use select/update/apply functions to create consistent vulnerability handling. Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 40 ++++++++++++++++++++++++++++++++------ 1 file changed, 34 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index a727f7998bec..de431f2bb012 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -70,6 +70,9 @@ static void __init taa_apply_mitigation(void); static void __init mmio_select_mitigation(void); static void __init mmio_update_mitigation(void); static void __init mmio_apply_mitigation(void); +static void __init rfds_select_mitigation(void); +static void __init rfds_update_mitigation(void); +static void __init rfds_apply_mitigation(void); static void __init srbds_select_mitigation(void); static void __init l1d_flush_select_mitigation(void); static void __init srso_select_mitigation(void); @@ -197,6 +200,7 @@ void __init cpu_select_mitigations(void) mds_select_mitigation(); taa_select_mitigation(); mmio_select_mitigation(); + rfds_select_mitigation(); md_clear_select_mitigation(); srbds_select_mitigation(); l1d_flush_select_mitigation(); @@ -215,10 +219,12 @@ void __init cpu_select_mitigations(void) mds_update_mitigation(); taa_update_mitigation(); mmio_update_mitigation(); + rfds_update_mitigation(); =20 mds_apply_mitigation(); taa_apply_mitigation(); mmio_apply_mitigation(); + rfds_apply_mitigation(); } =20 /* @@ -614,22 +620,45 @@ static const char * const rfds_strings[] =3D { [RFDS_MITIGATION_UCODE_NEEDED] =3D "Vulnerable: No microcode", }; =20 +static bool __init rfds_has_ucode(void) +{ + return (x86_arch_cap_msr & ARCH_CAP_RFDS_CLEAR); +} + static void __init rfds_select_mitigation(void) { if (!boot_cpu_has_bug(X86_BUG_RFDS) || cpu_mitigations_off()) { rfds_mitigation =3D RFDS_MITIGATION_OFF; return; } - if (rfds_mitigation =3D=3D RFDS_MITIGATION_OFF) - return; =20 if (rfds_mitigation =3D=3D RFDS_MITIGATION_AUTO) rfds_mitigation =3D RFDS_MITIGATION_VERW; =20 - if (x86_arch_cap_msr & ARCH_CAP_RFDS_CLEAR) + if (rfds_has_ucode()) + verw_mitigation_selected =3D true; +} + +static void __init rfds_update_mitigation(void) +{ + if (!boot_cpu_has_bug(X86_BUG_RFDS) || cpu_mitigations_off()) + return; + + if (verw_mitigation_selected) + rfds_mitigation =3D RFDS_MITIGATION_VERW; + + if (rfds_mitigation =3D=3D RFDS_MITIGATION_VERW) { + if (!rfds_has_ucode()) + rfds_mitigation =3D RFDS_MITIGATION_UCODE_NEEDED; + } + + pr_info("%s\n", rfds_strings[rfds_mitigation]); +} + +static void __init rfds_apply_mitigation(void) +{ + if (rfds_mitigation =3D=3D RFDS_MITIGATION_VERW) setup_force_cpu_cap(X86_FEATURE_CLEAR_CPU_BUF); - else - rfds_mitigation =3D RFDS_MITIGATION_UCODE_NEEDED; } =20 static __init int rfds_parse_cmdline(char *str) @@ -702,7 +731,6 @@ static void __init md_clear_update_mitigation(void) =20 static void __init md_clear_select_mitigation(void) { - rfds_select_mitigation(); =20 /* * As these mitigations are inter-related and rely on VERW instruction --=20 2.34.1