From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [198.175.65.17]) (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 9FA9621423C for ; Sat, 18 Oct 2025 02:50:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=198.175.65.17 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760755825; cv=fail; b=YCQQfJ7KxgYvGYiY7ZiO20Jy+9HwjsJBRjLYhCl0iaHbhzYwdin4drYpQANLpzikDiwbkWMvXeVb1JFvFNaPpP2ldA+J6AhW7RxzbJn6RLlC/pXPNO4x88rCLRRJtg8gO1UszGNT7el7YwKrxEWX51ACtyAuOLP7x78rXn+udHM= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1760755825; c=relaxed/simple; bh=3vLm+Tr94cQ8DJLghmWhZnDPT4VmSeM5oMfpI/wvzPs=; h=Message-ID:Date:Subject:To:CC:References:From:In-Reply-To: Content-Type:MIME-Version; b=oorAL6vDUr7/gg6bzlLz2m2JdrVic/UVT2W4PB2e9sVwhHKTMFSo9kakE2LGoSi/8EZekTWNxBgiFkNJy9J7IiG6ctSLxLM5z6/5YsOQy+G+8TUN0gqLfCkQhCZz//dtYvuizkaPck04+pLhpoApMbZESzciJaorBd6Lb8QMCWs= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com; spf=pass smtp.mailfrom=intel.com; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b=N8R/x5ww; arc=fail smtp.client-ip=198.175.65.17 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=intel.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=intel.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=intel.com header.i=@intel.com header.b="N8R/x5ww" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1760755823; x=1792291823; h=message-id:date:subject:to:cc:references:from: in-reply-to:content-transfer-encoding:mime-version; bh=3vLm+Tr94cQ8DJLghmWhZnDPT4VmSeM5oMfpI/wvzPs=; b=N8R/x5ww8po3yIu6xFwCcCTgksYswo1fhNfM5cvh+PwPbutA3Wnb5h7N lvxCN60vb3gVRWj3paVT2xnhKN4ciBoch5pxK0eJos9TeugtRwFwdidNu TEAdMRYmcZpD4G5jNCTo3vtpi+rFb0I3NMbm1b/ZZ0WSC9XIUwngCmDD+ 3rTLur53cYP3j/AUT1SSMHK6a5MaEoTafqVt+aSMQ5CvaanoEU3gyxYka WU5/Ruzng/HHdpuxfzADa2/BK+IytZIxSyx8VjFgyT1i9Lt5VvP/lfNgA 0YykBrIrqUCBZieVT0A3qijd4MiWO0OEAPnt1Rg8a3B5BEZ6dslhvjq7t g==; X-CSE-ConnectionGUID: xHmT/7CRQiG4Wa8Ab0FxUQ== X-CSE-MsgGUID: eiue9SeFQVWPSpq1Oi1P5g== X-IronPort-AV: E=McAfee;i="6800,10657,11531"; a="62886742" X-IronPort-AV: E=Sophos;i="6.17,312,1747724400"; d="scan'208";a="62886742" Received: from fmviesa006.fm.intel.com ([10.60.135.146]) by orvoesa109.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2025 19:50:23 -0700 X-CSE-ConnectionGUID: di2+ehirRJC5M214d14G4A== X-CSE-MsgGUID: 9lpBTwGeR4214a1fjS9j/w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.19,238,1754982000"; d="scan'208";a="182820075" Received: from orsmsx903.amr.corp.intel.com ([10.22.229.25]) by fmviesa006.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 17 Oct 2025 19:50:22 -0700 Received: from ORSMSX903.amr.corp.intel.com (10.22.229.25) by ORSMSX903.amr.corp.intel.com (10.22.229.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Fri, 17 Oct 2025 15:44:17 -0700 Received: from ORSEDG903.ED.cps.intel.com (10.7.248.13) by ORSMSX903.amr.corp.intel.com (10.22.229.25) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27 via Frontend Transport; Fri, 17 Oct 2025 15:44:17 -0700 Received: from SJ2PR03CU001.outbound.protection.outlook.com (52.101.43.19) by edgegateway.intel.com (134.134.137.113) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.27; Fri, 17 Oct 2025 15:44:17 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=q8QcOp1kZIYwG93NGwP19QNX2snRZDiwkbxPYWSHs4gncqMbUrwLE+7t5KsjZ6glYvCVbZs55sEIfCBo3btHcUlgcno4d+zecJVnQzbQPNbLXyy1usF2ul3oaVq/HwlZL97g/7F1RV5wZnfm36N5IDz9eF8NzmpAAE49MbV6Ax4QP0diqLcYFgv0dVGGXAe+pi84RnhSKOsAK8EBGm32PrWaiZcT5HWKq5ZhxO0zS/8lGgrqcFIShJsbBB/avVXWI/pFJ99v6LUDNJPEhpRr2hYd2rek5LnUr3GmdHAiQru5fvyxRCy++cONWPAylsERN6fIMt1f4NGVFKpRJh8NPg== 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=LhMtbLarULEYgLoeDoVQSsBhjwRv0UCbjYJB1gSVwvU=; b=ysb9l3WVwCkgxI7QgfQyz6ACb7vU8HAvaDagf9nLjuA9shwuOeWVgI1iTNuG4jrBNQvB7l6KUtByX9Ke2Z5/CgLPMlevScDRuqEeqBsDxL2wQIs3HdSaQuzwuwcloSGOt0sKXeSnlJG8QYZkEtevHHi/iuxd1YwDvELfFhV2+z5us+wXf5qUwwB42LL0hw4+xe4IDRKF7iDQHjqo+9HOPWLQJmX4sGWiNRbgR9uOXRqLuN3i6IRQjYOp/43LuY0500rh3W016dKqh4cFbGEtmohFRGLPMXlhejZZqscBOxu/MAjjGr8OfmHp5IKKrmUPmNmguqh8sarwyBu3ZxZenA== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=intel.com; dmarc=pass action=none header.from=intel.com; dkim=pass header.d=intel.com; arc=none Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=intel.com; Received: from DS0PR11MB7997.namprd11.prod.outlook.com (2603:10b6:8:125::14) by SA2PR11MB4860.namprd11.prod.outlook.com (2603:10b6:806:11b::10) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9228.9; Fri, 17 Oct 2025 22:44:14 +0000 Received: from DS0PR11MB7997.namprd11.prod.outlook.com ([fe80::9105:2b7c:b256:7a6c]) by DS0PR11MB7997.namprd11.prod.outlook.com ([fe80::9105:2b7c:b256:7a6c%7]) with mapi id 15.20.9228.012; Fri, 17 Oct 2025 22:44:14 +0000 Message-ID: <9f0ff555-860c-4e3a-9865-b921b0f7d187@intel.com> Date: Fri, 17 Oct 2025 15:44:11 -0700 User-Agent: Mozilla Thunderbird Subject: Re: WARNING: CPU: 1 PID: 0 at arch/x86/kernel/cpu/cpuid-deps.c:123 do_clear_cpu_cap+0xdc/0x130 on Intel(R) Atom(TM) CPU N450 system To: Dave Hansen , =?UTF-8?Q?Lauren=C8=9Biu_P=C4=83ncescu?= CC: Salvatore Bonaccorso , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , , "H. Peter Anvin" , "Chang S. Bae" , Andi Kleen , Eric Biggers , , <1117002@bugs.debian.org> References: <45a02791-dcb9-4d70-ad77-4fdcbf556c15@intel.com> Content-Language: en-US From: Sohil Mehta In-Reply-To: <45a02791-dcb9-4d70-ad77-4fdcbf556c15@intel.com> Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit X-ClientProxiedBy: BYAPR02CA0016.namprd02.prod.outlook.com (2603:10b6:a02:ee::29) To DS0PR11MB7997.namprd11.prod.outlook.com (2603:10b6:8:125::14) Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: DS0PR11MB7997:EE_|SA2PR11MB4860:EE_ X-MS-Office365-Filtering-Correlation-Id: e4d61fb5-e8ee-4505-68d6-08de0dceb261 X-LD-Processed: 46c98d88-e344-4ed4-8496-4ed7712e255d,ExtAddr X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|376014|7416014|1800799024|366016; X-Microsoft-Antispam-Message-Info: =?utf-8?B?RTNHOWwvNmhPb0M4Z1JIcVRyZ3F0clJtY0VYajZOUWd6bVpLY3BoYW0ySEVx?= =?utf-8?B?UENTYzlpTWtZZStLUTJEaTZETlA4bWZQcUhaMjVaNUFVdTJRMFBwVXZQVmNS?= =?utf-8?B?cDkzbURBdFBnNUpzTWMzRXoyRDNEZjJBSlQ4eGlIRXAveXNsNU5hTnBOa1dB?= =?utf-8?B?Q0RmdzB4UXIwc2ZnWlJISkQxOHQrRzdXZjM1dis4MzN1OGJhajVpUXo0Qml5?= =?utf-8?B?bmYva2pmSUJoanNEb1JpbE0rT0tDV1BseUp4NERsM3AwYTBRWUh4T0pRM1dV?= =?utf-8?B?OU82ZmIrWVJCWWdwTXRFMTZCcjJ1dm5icFB4WVNaZTVrdU0rSVg4OUpkcFJX?= =?utf-8?B?eC9UMk1RaXFHK2RWOWlpeFJ4bDRCeS9pZW1YWTFWMTl0Y1U4Z3NLWFlvZWc4?= =?utf-8?B?UU5xMkJGTDhwcG9ZSTVOUE5JTkNldXR2citxZ2xxUTlWVzRqRm9oSmFNbEVn?= =?utf-8?B?cm0vNzBsazZyZ2dTVUhRVUhRMi82L0ZLbE5PR3RJbVU2czNRSlBuNGNZQVdl?= =?utf-8?B?UjR5VTJiKy9SYVZ0UkVYYmtrZlI2amVZK3drQTZpeFlHRFl6MmtFVTc1UjJS?= =?utf-8?B?QWtXejhld0ZVUUN1aDhNSisxcjVGNDZrYnI4MlhicUVQcWtmclZXc3JjMUo4?= =?utf-8?B?Q2UrVnVIQjNqU1prOTRSbGhxeUFMbVVMR2FmMmErSjJSbitnbW83aXdBdEll?= =?utf-8?B?Tk5MSDRIUjVFb2k5ZlRBbW9waVNEL05Mck50UDg3dGdVUVJteUV4aFQ5QlEr?= =?utf-8?B?ZnFkMncrZkJELzFzbXFxWUF5N3BWWDVacW9qL1E3VFpwVDZqTWJKU01rbVZw?= =?utf-8?B?czVCTVhLMzd4Qkx6OG5pa2lPMmoxQlliU2tncEg4QnhOMmZ6eEdnVXJjd0xn?= =?utf-8?B?dnkrZHdXSDBlMWc4T2JKWU56Vlp1YjNoaU1rSDJ1cnFnbDVTeFM3VWNZTGxK?= =?utf-8?B?c2o1VWQ3RjRwRWlEZENVaWczNy9zMWJIOVlsbVRmb3RpZEc4VUxGWE91UFlw?= =?utf-8?B?OTVyRjhLTm00TS9OZTUxUlEveXV1RitDOWQ4eUh4bk05U2RFVkZ3Q3EzQ0RH?= =?utf-8?B?OUlkc3p1N2Y4WUQwUDJJNXZuOE9ZQVptVi9SVUNMMFZTUGdEK3hmQUJIeWNz?= =?utf-8?B?aVhINm4rOHRnNGxaODdsTkxMN1cxRVNYQ1d3YWFDZ0xZV0Ezd1BOTWRQRjc5?= =?utf-8?B?Rmp5U0EwUnlRWWpLUldxVXlyWTlIbUZtNnpRSGJxY2ZrY1lHeG1LN2tPTmU4?= =?utf-8?B?SE95czdVeXRHY0ZXRG0wZ2N5OG5JcWhVbWxNeUFBayt1R1NZanpHR2hFSTd6?= =?utf-8?B?SU4vN0VhOS9BbWU3V2tXWWZRdFY5anJVYjFFQ0Y4cXFVaXNpVjhObHRkS0Mx?= =?utf-8?B?T3NOZ2dHZklEUTBtNXhEVGJqVGtaZUxqOG9aeVJoUGw4QXNnSTVlNEM3UGRV?= =?utf-8?B?Q0h5SklocTRoQUwvN3o1emJKSGRkYzlUMXQ4WUNjdlZKSStSamZKWjR6SHYz?= =?utf-8?B?WVdERWwvdEVnQnloRHBnU2ZwY2JaOWErQVNPYUpKcWpxalUwUGxLVjFTeHli?= =?utf-8?B?blV3VG9ZWEc3ZFlCeFYxUDZQTG5EdUdCdVZtZmJhalpuV0NPK3VMc1Q1djhK?= =?utf-8?B?YS9aQWdwNmtHWEVyN1FxMzNUWFZIcFBncGVaeDc4Y3ZUWGlVZjJYVXdLdlZ0?= =?utf-8?B?LzcvUzJPVkJXOTZ4cHJ0RXhqbU1SUUNRZ0xCY0pDOGxuQnVDYkpXRGJBdVlo?= =?utf-8?B?VnhpUVUvalVvQlM5NEFGeHNiNTlFSjZkaW02cUJkM3NGb3R6eGt4Z1hUWGtX?= =?utf-8?B?T3hYMHJaTzFQQ3dvcTRZc0Y5Wi90UzRSWVgvYmEzWHRIUnkzSHkyblhoQ1My?= =?utf-8?B?R3dTeXltaFgvSzVST0NvbGNMbTJVWVBpRnMrRm9pSzhyd0ZrMTNJMGQ5MjVE?= =?utf-8?Q?Wns0Dsvo2WJC27mUMIOUP74Pno7+2bev?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:DS0PR11MB7997.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(376014)(7416014)(1800799024)(366016);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ekl1SnNxeGVGRTkxTzJlVTFicUplUmFmbThhVUd2TFpZaFhPRkdrcnd4V1N0?= =?utf-8?B?Z25semZCWkttallmMVUwaFZvL2tOOW00enBhc3Zvd2FMYzlwdHI5L1FPTldM?= =?utf-8?B?VWFRcVJvZmZVMjYrZW1rUlI5a3ZWcC8wVVptcjV3REVXVVNTZG1yaWVyWW9B?= =?utf-8?B?aldGcHdYRDU5djR5SVljN2dsSStLcHg3am5MNlVYSFhSa2toUzJQa3RRV1NR?= =?utf-8?B?Y0dJTFRNNjJka21CWXA4SmJib2dPOWhYeUR6b2FuYjc2cExFam5XdEFlTVpU?= =?utf-8?B?UVFOcUFkZ1lqUUV6dEhnVjZ3WTcySXBOUEh3UWZtTmpzQWdQaHdMbjNmb3F4?= =?utf-8?B?eXdvcngvRUpVUGxQZXVhSkFZa2hLOC9BVEJOaHRCb21HekZiT3QxcEZUT0h4?= =?utf-8?B?U3hIRVdQSlI3VWV4alN2bXNXUmpIZ2ovdmRzRU04SnpNem8rNkhDejdwWC8r?= =?utf-8?B?RXljOGc3ZVl6VGxreWEyc0FOd0tSVXh6cVVUaTZxYUlqWjkrKzVWcGZuSlBx?= =?utf-8?B?SmQ0VFdQUC9OLzRqTTIwdUhMdHVPb3pwNDUzTzNiMURyeC9nV3hodE5sVmEr?= =?utf-8?B?OWtQSHVmQk1ZWUVONWVENTVWb0hINit4T2oyY0NUODZCcm84TEdMb05sK0hT?= =?utf-8?B?RDdBM0orY2dzRVRpK21Vd1ZodWFHeUdwTTJjWVVJQXhFamllN0I1OFZzNm9x?= =?utf-8?B?dWVCZ09DVDN4Q0hjRFZGU1hMWHcrMHBqLzN5aVNKeHZLTmlDd2dneWdjdTJN?= =?utf-8?B?SjZ6M0NWRTEwbUpzWWVMcUtmYWd4cG01RWNFNUhINStvRitRYldKbFJ4cll4?= =?utf-8?B?Q09sNUpQZ1NrS0JndUtEbmttRWtOTmIxK25BUUVRY0RNVDQ1TXEzL1FHc2ZY?= =?utf-8?B?T0ZGWG5tUUlzTkZVaU90SnVLTUU5U3EyZFVFMy8zOElZK2E4ZlpCaFAzU2hh?= =?utf-8?B?Qm04ZmhwNkxxcjVaK2RBTVZVYjJPbXJjZ1FnR2x3Wkl0WEdjbktia1JWQm9N?= =?utf-8?B?OVZ3REtDcEdQeXVqekJkU2w2RWxaNEg5MlZpTk5kVVBpSWNHM0U1T1R5bThT?= =?utf-8?B?WjRmY2FEYnFRdEpoWCtiYzZVYm92Unc2VExnaGQyS2pkT2ovRUYwajJieUJY?= =?utf-8?B?aDBwTDliOHh0RHdtemRKY2lnSC95WVhmNEVEK3F1eWdUcTc1YkRPOGg3blZx?= =?utf-8?B?d0g1aDdlMVlERnlETWM0dUNJNk9mUDNjMUpsR2UweDhLZ0ZzdlNLVCsyOUNL?= =?utf-8?B?R2o3Ri8yWFplODNWVmdkSlJOY0lOL2FVb0FLQjBjZ2VGNE1aZVdBaEpURGR0?= =?utf-8?B?dW1KNk10anlRK1pQQzg1VUFmNWdoT2Q2bUZWVVNQNmpWZXFSbWVRSnBCWVJ3?= =?utf-8?B?TzhoWlZBVWs1VkkyUm04aWlNUmEybnRZUTk4TFRETFB3T0VDbVpqdlc0MVVQ?= =?utf-8?B?VkZURDJ1K3IwbWZod3FDOHhnRWJXamdlWHFIcDhsV2MzeHhCVFQreTVGVkJw?= =?utf-8?B?RlVvbjZ1am1MWEE0RDVRY1JjV3FzZUkwZXhtYk5iZGgvaVlsSDdhMm5tVkRW?= =?utf-8?B?UjJZMDNQdUtpQ3ZKcWVOVTF5OU5FbStIYjZXWWwybVBMUnhNMHN1REZYYzJD?= =?utf-8?B?dklJOFNFRUI1TzJYclhIK0FmOXpnWG9HL29UQmVkV0xkUC94YzU4RENUNGY4?= =?utf-8?B?dEdLbElCemQ3YWdtVEZ5R3JaS2diazJjWTlzTU13cFRWbUJmb1FpUmlwU00y?= =?utf-8?B?UHJxN2tZQVp6L3pwVkdvK3J3NEZEdnBKN2pudkNYTzRvcTRMVUFDR2RLZUds?= =?utf-8?B?d0ZzMnZyQjZuc3F3UUE1K0VzbGttNVl0dDRXKzZYbGNrazZ0S0JNaVlteG5M?= =?utf-8?B?ZEVhWnFwSTNjQXFWaG5qS29pVHVKbWpRTFdNUnNHRWJoUVF6b2RjL3V2aDYy?= =?utf-8?B?bUpHcEUreVBwNFl3b2MrdjZUOXdWVTZKL3JDRUxnQmNuOER5T0JYalJ2WFFH?= =?utf-8?B?bWk2eGcyb0Rad0NJcEJaN2hNKzhNQ0djVGpOWWFLM1ZuM2pZTGRncFlPZ0JZ?= =?utf-8?B?R09TSjNiN3lFZjVmL2t4UFgxb3JMNjZ0KzA0YVJZNkFIbUw5ZUlpazhhV1FT?= =?utf-8?Q?cRR3qpBgEF5O+V9wahz3R3V7d?= X-MS-Exchange-CrossTenant-Network-Message-Id: e4d61fb5-e8ee-4505-68d6-08de0dceb261 X-MS-Exchange-CrossTenant-AuthSource: DS0PR11MB7997.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 17 Oct 2025 22:44:14.3061 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 46c98d88-e344-4ed4-8496-4ed7712e255d X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: YQNtaOZ1C1LrrUNp+breY9nYBj3oO3y+kF8Hp/rE8XAlgp14VE5ctbjElBKuWczfb84c85ekJc+VDlezA7dk6A== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SA2PR11MB4860 X-OriginatorOrg: intel.com On 10/17/2025 3:01 PM, Dave Hansen wrote: > I'm not quite sure why newer kernels are complaining. The > "alternatives_patched" check has been around since ~6.10. If someone has > some spare time on their hands, they could bisect it. But I'm not sure > it will change anything. > I would bet on commit 15b7ddcf66fb ("x86/cpu/intel: Fix fast string initialization for extended Families"). It started honoring the preference set in MSR_IA32_MISC_ENABLE which seems to have unmasked this issue. The commit has the following snippet: "X86_FEATURE_REP_GOOD is cleared in early_init_intel() if MISC_ENABLE.FAST_STRING is 0. But it gets set later on unconditionally for all Family 6 processors in init_intel(). This not only overrides the BIOS preference but also contradicts the earlier check. Fix this by combining the related checks and always relying on the BIOS provided preference for fast string operations."