From nobody Fri Dec 19 17:01:13 2025 Received: from CY3PR05CU001.outbound.protection.outlook.com (mail-westcentralusazon11013000.outbound.protection.outlook.com [40.93.201.0]) (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 340F03081D7 for ; Mon, 13 Oct 2025 14:35:29 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=40.93.201.0 ARC-Seal: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760366131; cv=fail; b=rJrAtK5xjYMh3Zh+A4919sgu3UspRvwDUS44sDb41UgcQRBN4NLV7RnOavL+SPXqSVAhY3QT9Z+MVWyKpjh2MA5mgNUgxRN5JKZGEVTf+FfQEpvoRklO/FZQejHlzxhU6g13SRnRJZnC0H3y6u8WZpYC9fqcb1c983TftXqrmkA= ARC-Message-Signature: i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760366131; c=relaxed/simple; bh=gnYCgii+whL3aqL5OGcVub4rbWIAWkIZ9euOHRBUkQw=; h=From:To:CC:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=aB7VpN1bc+f2A9rv43Z6dO1ViXiWkQp6qL5sg7T1SX/qeLcH9+obZ9E2FYAZMIK6nj6euzRCkppqN3bbai5Zt3Zp+bMYfW/4n4j5+UukosZrkbs3MAyQEFjp+FBTHhiMQtLg0CyTzEi13vxoQk9WFHGNuQ/2UFmGenXjvc6JvjM= 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=ei/Wwz9A; arc=fail smtp.client-ip=40.93.201.0 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="ei/Wwz9A" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=TzFdKDO424ELRVFqdfHpfdwrZAGOoqAcGtWt6mvdc9KTKQ1VTrUMuhtxqm7E80q1OP0kaOTIkPISaqLrGIrXLyinUCokoQKWzPWL3d3zorxm2MxhVvUDfaQiR2v85akp4UJX17oVV86R3rJd3pVNmSAHolS6Z4aTxYZGq6jlRij/d1vNddrsBTIi5Lx3U9537cwuHWxcg6TZqA2qKcEmVnsnzvHqMOTTlEJTEYYHqn1NCubanntT+8qAMI/x1bYrHdJxJ1mdHTsj1eqUoeJO/iTiILVPQP7hH1UqX4fFL1Kp68rKZtU8UDAnH87F9s+E3uKNqCve4kr3dApIn56rcQ== 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=eifWsU6LUbv+jSM+HUEkLHKU+HA3dk98cm4FSQkmrcs=; b=J0rHO66jJvf5MnJlS2h0uIo9R6fXrf0DJdbMvzv2aLpJsriumLWicYTvzt+NuId1yvyTmbP9VXgCEZWJd3vNU9hzfglmzh51mAIw2RoPZICilV942sRY1oHJqAaMHaCyOiiKnDNyr9oax5bj/yW1D19X3bWEZWyCyHGHysgnkUMBnR4IUjbBDPDsmeUcqWNVcP/gbUH2iS7kT7SlCL2fawEh0BGu56O0QUEUDyqZtWl0BHuQ/UFgBjSVXFf/qRbe0HF0hBwAH4SlH3zFIS72fuuXjGUSCsV3/N0RvFH1LWkpup0NfOf3rygcW2TpyiEGr2qXGcybD4mnnT8zQvXvow== 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=eifWsU6LUbv+jSM+HUEkLHKU+HA3dk98cm4FSQkmrcs=; b=ei/Wwz9AZh/eF0djlKU4/tjW9czOlXiR+FFDsb5qgxr/XF1oLtSl4aECUX8D78EncXb94zm2FFDxkQERgEGRr+rNq4x+uSWgy3XeBKdiHaP7MYFL4fqVM7KYAiHk2DT2GcYx3iQ+hdys+w5tKm0HO2aPVtJO2/AMUG4nCYzUuok= Received: from PH8PR02CA0029.namprd02.prod.outlook.com (2603:10b6:510:2da::27) by CH3PR12MB8257.namprd12.prod.outlook.com (2603:10b6:610:121::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9203.12; Mon, 13 Oct 2025 14:35:27 +0000 Received: from SN1PEPF0002BA50.namprd03.prod.outlook.com (2603:10b6:510:2da:cafe::54) by PH8PR02CA0029.outlook.office365.com (2603:10b6:510:2da::27) with Microsoft SMTP Server (version=TLS1_3, cipher=TLS_AES_256_GCM_SHA384) id 15.20.9203.13 via Frontend Transport; Mon, 13 Oct 2025 14:35:26 +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=satlexmb07.amd.com; pr=C Received: from satlexmb07.amd.com (165.204.84.17) by SN1PEPF0002BA50.mail.protection.outlook.com (10.167.242.73) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9228.7 via Frontend Transport; Mon, 13 Oct 2025 14:35:26 +0000 Received: from tiny.amd.com (10.180.168.240) by satlexmb07.amd.com (10.181.42.216) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.17; Mon, 13 Oct 2025 07:35:26 -0700 From: David Kaplan To: Thomas Gleixner , Borislav Petkov , Peter Zijlstra , Josh Poimboeuf , Pawan Gupta , Ingo Molnar , Dave Hansen , , "H . Peter Anvin" CC: Alexander Graf , Boris Ostrovsky , Subject: [RFC PATCH 13/56] x86/bugs: Reset SRSO mitigations Date: Mon, 13 Oct 2025 09:34:01 -0500 Message-ID: <20251013143444.3999-14-david.kaplan@amd.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20251013143444.3999-1-david.kaplan@amd.com> References: <20251013143444.3999-1-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: satlexmb07.amd.com (10.181.42.216) To satlexmb07.amd.com (10.181.42.216) X-EOPAttributedMessage: 0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: SN1PEPF0002BA50:EE_|CH3PR12MB8257:EE_ X-MS-Office365-Filtering-Correlation-Id: c2573e44-4365-4f96-1a55-08de0a65c07c 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?ls3LTOCnnwYIJcwKVgUjm6JE7BMIRfAnHfhHBlR9Y9WXruA6HDMiI/oNwIHm?= =?us-ascii?Q?+spRfC/7hVKGbqqsiWjndbzvLBXS6FDx6u4tWmONedk9WEz0a37O5aavdPf5?= =?us-ascii?Q?K5BbchGS51eFyKPfOv7bLQpNuoCfqIJxnmOjDdh8P91Uic76Gfbml3tJxujN?= =?us-ascii?Q?aNX7RZnIpn8uoIgfSbp4KWK39XYCvwixNLpYQ7VZoF9WPdeZ2iOJDe/u+vrD?= =?us-ascii?Q?+ZU/8DSYJ6KsHeqUUSLpZisheVCK4i2I6Ika78C0PuoB4YpPvqnsANdRYM+J?= =?us-ascii?Q?EjiCMaquW7qTh0vj4Hw0Ht69qugDpWsd4linDVlLYg/a0g1PhfWucxxPjDMW?= =?us-ascii?Q?HtoB+1hxKTKYlQ1AXnK3rKqhdzmHB3QS+ziaFhPRL9DDCSGQ7R8FZfrAwVmb?= =?us-ascii?Q?n5xqrNWRisTKbkF6pqDXvBaq/a8UroWZ2Se7ewKFf58BCyUqIx+NrnvIlTe+?= =?us-ascii?Q?lMtFeUfXuxHyrFJQ/3JKZUSxpzwSQbEDbsfTImIM/CNN8k19hw5yvMPPytPx?= =?us-ascii?Q?WxRSFocfRkR4TJHp2aS888bmitgVxIV/jsKXTR0Pru8lf9H1Q7Yv14hUHcfB?= =?us-ascii?Q?QIzn5W/gLTPn/XPbiZG6Zu341phoV6xUbajGXE1IsQXU5NZWRthoeTLNb0dL?= =?us-ascii?Q?Q7pooYMwH0ohozqhns5xE+5oRS8Mjznvd37UBTGFfy74vhNPsTCOIlctOoIX?= =?us-ascii?Q?U7D4MMtOhvWt7X4xgEHA2/FvFDlVxcA0ZbuyBl7GnnwIPmpeoEHv4wmxWjIa?= =?us-ascii?Q?Rn4m/zT5A7qxjF5ajwphmmzjT3FpUZ3n9MOecWpSsJJe58Bo4PowPvx+wc3S?= =?us-ascii?Q?5plEdeJPzulhVUG/KHO7uh1PRCOQyR9r6gz4LYlQBGUpS8RaeNhfTWXzaWYo?= =?us-ascii?Q?pdoSB6DsBYpzUlb9fmzQL56Mdsj09bdMDQ3I2wOahC95bG8PttUi18/2y87i?= =?us-ascii?Q?WUuhRJ9iEhZP4BARwAV1JPBJ7nynfYC8QwDCQHMgNEu3Z/Z/smIct7fbBY3q?= =?us-ascii?Q?WL3FhNBJT4yzTdmPzYUcXx7yM/W5fyASdxbrtK3Vo8o+fnkv2cs48Rb2NZDp?= =?us-ascii?Q?1XEBMY72J3IpCPaFxLdO4R29lK5Tze+OeMNYmYMbhCHJIV2sZptwc0zM7dL+?= =?us-ascii?Q?pR4By41K9DEZ9h94Z2iLQIx6avBC6moxDomzaB6NIHSc93ABAgERGDANQmP7?= =?us-ascii?Q?tWpZep5JqbUu27VaegpnPPWrfBeb/+wQpOJG4muqsItEnKhgcMGnBf3ZRuUb?= =?us-ascii?Q?2yzF0gDGHjnExvGy0/qm69Mx2ktwQUDnVGLHYpWQoEc2zxho/jd6YM0C1Lao?= =?us-ascii?Q?bU2DVftpGVwryssA+4ImRGifMnpOUAPWvO7zHpOK8kyt4rfvYX2/SQiAAoLv?= =?us-ascii?Q?FA2BBGUCYkyhVKUaU+iYQF1SgLNSW5Xxm+z5vkVb5h+W/1280wND9WmvzEGq?= =?us-ascii?Q?oXqsv0UqWCHezyzjZx5JOIbQDEeQl8x4iy08rwl/GTIrN4kNrnWDZ8yUKUFX?= =?us-ascii?Q?R0QgGHBfaWrH8eQohq6nS9e9OHNuU+C2WOMrJxo/uQU0yFuzJZr4tZ9pIDwb?= =?us-ascii?Q?xRPlVhsAeFMkJqDWNZw=3D?= X-Forefront-Antispam-Report: CIP:165.204.84.17;CTRY:US;LANG:en;SCL:1;SRV:;IPV:CAL;SFV:NSPM;H:satlexmb07.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: 13 Oct 2025 14:35:26.9878 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: c2573e44-4365-4f96-1a55-08de0a65c07c 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=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SN1PEPF0002BA50.namprd03.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR12MB8257 Content-Type: text/plain; charset="utf-8" Add function to reset SRSO mitigations back to their boot-time defaults. Signed-off-by: David Kaplan --- arch/x86/kernel/cpu/bugs.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+) diff --git a/arch/x86/kernel/cpu/bugs.c b/arch/x86/kernel/cpu/bugs.c index 9a9d5309aa56..112553058ccc 100644 --- a/arch/x86/kernel/cpu/bugs.c +++ b/arch/x86/kernel/cpu/bugs.c @@ -3312,6 +3312,21 @@ static void __init srso_apply_mitigation(void) } } =20 +#ifdef CONFIG_DYNAMIC_MITIGATIONS +static void srso_reset_mitigation(void) +{ + setup_clear_cpu_cap(X86_FEATURE_RETHUNK); + setup_clear_cpu_cap(X86_FEATURE_UNRET); + setup_clear_cpu_cap(X86_FEATURE_SRSO_ALIAS); + setup_clear_cpu_cap(X86_FEATURE_SRSO); + setup_clear_cpu_cap(X86_FEATURE_ENTRY_IBPB); + setup_clear_cpu_cap(X86_FEATURE_IBPB_ON_VMEXIT); + x86_pred_cmd =3D PRED_CMD_IBPB; + x86_return_thunk =3D __x86_return_thunk; + srso_mitigation =3D SRSO_MITIGATION_AUTO; +} +#endif + #undef pr_fmt #define pr_fmt(fmt) "VMSCAPE: " fmt =20 @@ -3925,5 +3940,6 @@ void arch_cpu_reset_mitigations(void) mds_reset_mitigation(); mmio_reset_mitigation(); srbds_reset_mitigation(); + srso_reset_mitigation(); } #endif --=20 2.34.1