From nobody Sun Feb 8 16:31:14 2026 Received: from NAM12-DM6-obe.outbound.protection.outlook.com (mail-dm6nam12on2082.outbound.protection.outlook.com [40.107.243.82]) (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 B49A923F387 for ; Mon, 10 Mar 2025 16:41:14 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.107.243.82 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741624878; cv=fail; b=C2WgJ+zZ9IjYXlTLoEHDlWQilneT8JJw5LPonl3/ukWY70pYDfMAU4i7vJFvH0kE4H+5oiQdSoq/NmOzScYA/KWYvDDc1ZpLbNxDC1oUm7B1bY0I6IErQO78jt0XGtTOCmO7W3qgusWySrknshzkNi+AUlf7F2UfE1flXf84Baw= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741624878; c=relaxed/simple; bh=/T/sA+MY98hjm3OGlVdiO1pYozwb4VswMVGWNEKHQy4=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=RsMhTWBNYJhOt95SXvgVQTtfv9P70lon+Er3uLZYGkALXCwuqRtM5+Q3g0DLKkDDIGGnsI2RqAB8q3tLmdMgS/9adO2CMvUgFkYkn4o5uJPJIe1Sdr/OAM1XgBDaG7KwC7NeECVdhsK61uBJZU2gP0RHyjr4IN+gooX5CYo5cmE= 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=fv9kbyao; arc=fail smtp.client-ip=40.107.243.82 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="fv9kbyao" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=BtUfnq7yzbVOH1BxxogQUvpa4+bP/flhjqiaZvwC75kKHUthP5ldOYPgmsxevBzscjlOtGG9sL7C2NJv/WUhfgzp7KGm8wn0J5yv0+B6vWtl+Jftd46cyOIiGv16zj81OyPc5Zz83UHCduKcIabE+RAjH8100N6+HnJIg8RzF2JFSa4wDASAnMh7IeWpJHLTLd61lkVq3RnAYIgQZXFKpyAtqrP5JO5SWxRDOkDA8JsaWaFqx97ixqoZ9zI3KPbG+78bTuv2pumzJ2v5+C7XHiMVtgPe8nKempO87Sss/k/CxGFRooNzhkUBu1Fj6nB2omHC6RqMInJelYrXwprSvA== 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=zzY7lei3myX9iNqa4UvZSSvztf2qd4T5w/8a/kP7Hvo=; b=DlI6mE9zcQwLqdwFb8tH/7eBfD97nFXF4lywL9Z1v0xhoterf9sOHKLTvlyzct4It4GyNs9UfiqE+QRv7Eh+9RKCSZJKUwQ99HxX2Bu6mSVDx125wJbXIFMSSYvhPeqGp+R2aWZjw+Vi7dplCUj+IaOi9kIYWckPTorBb7naCLvjKAJDqORCpCOjwYQtYtaGUjASy/9z1MvY9wYao8+VGygfHBqIOhz8BVoxxBOwnFqQMaRRoUlgfJkzHnix8xaUwNHUSabDYbTXqgfE28MTyRVCu9mP49S8LLbe/s3cZi/GrFfRfvfCyF/rV3EnlkBIyDB/enFmO9g0YR9KKcXIoA== 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=zzY7lei3myX9iNqa4UvZSSvztf2qd4T5w/8a/kP7Hvo=; b=fv9kbyaoDBNt5DPQwSriSZ4LVc8crsksPk6rE5P8hQop9Euk+uGkFXkyrbMnmsYvZdMzC5vvvIumm1hmCAncSVqJMxyXP1xT4SkbCUpPZ3FWg+ha9cGFbw2o8u4iTMGkyUou/SWnvldiqiejhlf/c9JucWvnK3AcR/hjLn12bjI= Received: from BN9PR03CA0087.namprd03.prod.outlook.com (2603:10b6:408:fc::32) by DS7PR12MB5789.namprd12.prod.outlook.com (2603:10b6:8:74::21) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.8511.27; Mon, 10 Mar 2025 16:41:10 +0000 Received: from BL6PEPF00022574.namprd02.prod.outlook.com (2603:10b6:408:fc:cafe::f8) by BN9PR03CA0087.outlook.office365.com (2603:10b6:408:fc::32) 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 16:41:10 +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 16:41:10 +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 11:41:08 -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 33/36] x86/bugs: Add attack vector controls for srso Date: Mon, 10 Mar 2025 11:40:20 -0500 Message-ID: <20250310164023.779191-34-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_|DS7PR12MB5789:EE_ X-MS-Office365-Filtering-Correlation-Id: c96d2b93-3734-40dc-1a98-08dd5ff25cea X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|82310400026|376014|7416014|36860700013|1800799024; X-Microsoft-Antispam-Message-Info: =?us-ascii?Q?dFZOgG/yE2aXFVAVTg4s4XrSsybYLfSWcaauJ704dym3M+Ux3ygPCj13IQkX?= =?us-ascii?Q?0p0eNrLRKggfa5qe0FmKWiPXwvA5yjdVA/pjh3j34txryrNbGwPcVzbQF6ON?= =?us-ascii?Q?tFwVV5QVXZTW7aQvCHeY90z1/2gnzP4GnUahX5pu95jjCi0JZoSjrfVDOmvM?= =?us-ascii?Q?9wGQ0hIBdYSh5K9M0VDZvgLSPNY9jFW/VCIb6hnmHkD43TC+kyChzICI1lPr?= =?us-ascii?Q?lARvDROQbhTGb+TuramMbUBCxgJmItfRtSB2fY0mAeap5p3LCKz5iviQesCp?= =?us-ascii?Q?AP4Ui153EGkRk3DU7i8ScQP7ar52//fErET7kF62LqcUEVH1DnExeQkjt2er?= =?us-ascii?Q?hpGQN/z8dFYk4w9xVfbQKs6hf+G0Nk48XN/VjoL1Z4qfs2cvYysUl1xPW6mm?= =?us-ascii?Q?rxXVgaMXEu33UQCAg7zVeTa0oSGpZxDnE7oGXiuHa7l3pWlcsaCxebdP1RLK?= =?us-ascii?Q?xsl3Afr6QGZi9LDFYoWOX/popvbvNojdBll2n8ZdXDwvjRzetmxlvlBREDcB?= =?us-ascii?Q?aIfleouTyBjOaiiWgxsFZZywTSQnNPQP+ynNw6O/5cYBGYWHubf79sHabKga?= =?us-ascii?Q?P93sGqf3FHZyYwnK1KmZ+ihcLaACfmU/okQcHQVzbhzM1PtWfpOGCopKxHij?= =?us-ascii?Q?0PGo74F6MTtIFmk3FThpQo7NHI2J5JaR2Io7m+n41na2YjQ6yssFoaGUu51Y?= =?us-ascii?Q?gfhgvR5PLE+72A4dNwG9tvm/qrW02qq4TmUaFwej9i9K+q/G/Kmcud94mkuq?= =?us-ascii?Q?K5JdCp9ouZVh5JR3JGul91Y0YhtTJN2SFpKMonPasHNf8XlMRMOOLv3IIFDX?= =?us-ascii?Q?pvj4BgnBGXvsxP7NvrSFe4N8uHfzcInO91/iNGoLboHZY9cp9TaJfiFjpy8h?= =?us-ascii?Q?81WEDE/cpSuRdo+Pw4QyqExUNNsqnlpAHn1iz26/+4sinreuLZJ6s6weoVBu?= =?us-ascii?Q?pkC75DPIVKKM/XrBoVPFgJQVGg1wsfGoDTv0gu47X1pknIK52nY8Er7sxbup?= =?us-ascii?Q?Uj4/KzI+YznqtespCkA5ZRaqoIpV+iAAPbDh8QD+2Tjv5KcFjZBRPI9tL+wN?= =?us-ascii?Q?6h2pwcR5NKXNWNRu6zlB4zc4wlk8huuQo9nxah0mHzL53CCiuHCiPbL2W+DU?= =?us-ascii?Q?oI4p9nBJKbXcobloMKh3lRGLTvXzVenA07zBb06MH3sUYhXiSv7h49neRzFi?= =?us-ascii?Q?qTW+uq2CQl7pERD4GcK+pDMQgy2/M/qETsKoJ6XDQrpL91FHY2DTuBKveQgs?= =?us-ascii?Q?CIjTGn8G3hM3hEAJvw7a1RTaLcAtX6INiOmgL8Yi6fwo1Sp+96zMMI7HpHRY?= =?us-ascii?Q?IAl8xQTNiARM/a2bEGxoHBQSzaHPL7FavyIHnvsWclAprSS0SvxfvGtXilOK?= =?us-ascii?Q?lPEsMIP7qf+CZJPlxKPaYzQhaEthVkBrXzaXOQLYn7OGho4E7BzjABB7Ih1f?= =?us-ascii?Q?gDKVOx8ub0j78Vltml/ebytuQLJGLRyXxeqKd3OPPYek2HZ3v/vMit9I1p6j?= =?us-ascii?Q?Sde0DEXcJJFJVP8=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)(82310400026)(376014)(7416014)(36860700013)(1800799024);DIR:OUT;SFP:1101; X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 10 Mar 2025 16:41:10.1580 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c96d2b93-3734-40dc-1a98-08dd5ff25cea 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: DS7PR12MB5789 Content-Type: text/plain; charset="utf-8" Use attack vector controls to determine if srso mitigation is required. Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 17 +++++++++++------ 1 file changed, 11 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index e38529f3022b..4e1fc1468870 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -2858,14 +2858,19 @@ static void __init srso_select_mitigation(void) { bool has_microcode =3D boot_cpu_has(X86_FEATURE_IBPB_BRTYPE); =20 - if (!boot_cpu_has_bug(X86_BUG_SRSO) || cpu_mitigations_off()) + if (!boot_cpu_has_bug(X86_BUG_SRSO)) { srso_mitigation =3D SRSO_MITIGATION_NONE; - - if (srso_mitigation =3D=3D SRSO_MITIGATION_NONE) return; + } =20 - if (srso_mitigation =3D=3D SRSO_MITIGATION_AUTO) - srso_mitigation =3D SRSO_MITIGATION_SAFE_RET; + if (srso_mitigation =3D=3D SRSO_MITIGATION_AUTO) { + if (should_mitigate_vuln(X86_BUG_SRSO)) + srso_mitigation =3D SRSO_MITIGATION_SAFE_RET; + else { + srso_mitigation =3D SRSO_MITIGATION_NONE; + return; + } + } =20 if (has_microcode) { /* @@ -2921,7 +2926,7 @@ static void __init srso_update_mitigation(void) boot_cpu_has(X86_FEATURE_IBPB_BRTYPE)) srso_mitigation =3D SRSO_MITIGATION_IBPB; =20 - if (boot_cpu_has_bug(X86_BUG_SRSO) && !cpu_mitigations_off()) + if (boot_cpu_has_bug(X86_BUG_SRSO)) pr_info("%s\n", srso_strings[srso_mitigation]); } =20 --=20 2.34.1