From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mgamail.intel.com (mgamail.intel.com [192.198.163.17]) (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 D01093009D4; Tue, 5 May 2026 20:20:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=192.198.163.17 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778012431; cv=fail; b=MwE0nz5Qasps4vr+rMU6DTLw33mEk9wajFb2ZuPE3/3G00KO7InszegwOnfXsn00VeAVlY3QssBAjgszdhLECbWA/Uia1rWM/slKsJ4WH7avEnwrthkOh3qDEqnNsGjJJdefbt4fTolDQaSkISX4A06nfbciZI0np3nKo2aS8JE= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778012431; c=relaxed/simple; bh=5h3re5tRAxHdmDuSREP1DsRkGTjKcXx5sdZfFTL1dbo=; h=Date:From:To:CC:Subject:Message-ID:References:Content-Type: Content-Disposition:In-Reply-To:MIME-Version; b=D8HD4WebXTqq1NoFOHJxr3L3PA/a5FOPg8QiFoytB6+rH+sWInFFOkjruOQi+7krwICTLsEwAZ3mU/RaFPIXl9B6LCIRWNi3/i7+QzrUdif57cQMOJ/N4DwBVsm84ZTgX33AW0Rjcd2lH5OIfkpS9d4Jx6+sxupzsad78jGt8rM= 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=m/4fdQSl; arc=fail smtp.client-ip=192.198.163.17 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="m/4fdQSl" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1778012428; x=1809548428; h=date:from:to:cc:subject:message-id:references: content-transfer-encoding:in-reply-to:mime-version; bh=5h3re5tRAxHdmDuSREP1DsRkGTjKcXx5sdZfFTL1dbo=; b=m/4fdQSlSSws0aaPfQ6nhQYNrCkS2cqGtxWyw/8em8oKnQ2Is9d1cEih cun1gU1hAefeShTQwK71n/jyjT7g0giTtgzLfzI5kHNNcGtqnlxipNI9Q CFVa2dTxihBcLNwUUdLVFSrBlVE75RQGXvoGh6qmyqQ+tMl2RAjwfd2Zu tWLZzy0M+mZDiAKlcbdaQg5UmJ1sJSbi1r+8SmhWN75lXEd9joTuaeCD9 lpmPF+RvysYJPOAKZVVvjjoQO4hGMlk0MQm88kNBGvSx/zCXzU+Jz/i4l s4gS33fk6GPBdPLMBMHUpRRypEnlfzerXIN1VKLR/NzNdGoRjpCa1pIDu A==; X-CSE-ConnectionGUID: 7IoadwprROOG1/6cE1u9/A== X-CSE-MsgGUID: FbBYRIE0TzylRADCYv2vLQ== X-IronPort-AV: E=McAfee;i="6800,10657,11777"; a="78756879" X-IronPort-AV: E=Sophos;i="6.23,218,1770624000"; d="scan'208";a="78756879" Received: from orviesa005.jf.intel.com ([10.64.159.145]) by fmvoesa111.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 May 2026 13:20:27 -0700 X-CSE-ConnectionGUID: cp2fDN31QrKSt1Ve8PY02A== X-CSE-MsgGUID: 50LuChvCTaatZ/xUGNbwGQ== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="6.23,218,1770624000"; d="scan'208";a="240905386" Received: from fmsmsx902.amr.corp.intel.com ([10.18.126.91]) by orviesa005.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 05 May 2026 13:20:27 -0700 Received: from FMSMSX902.amr.corp.intel.com (10.18.126.91) by fmsmsx902.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Tue, 5 May 2026 13:20:26 -0700 Received: from fmsedg902.ED.cps.intel.com (10.1.192.144) by FMSMSX902.amr.corp.intel.com (10.18.126.91) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37 via Frontend Transport; Tue, 5 May 2026 13:20:26 -0700 Received: from CY3PR05CU001.outbound.protection.outlook.com (40.93.201.57) by edgegateway.intel.com (192.55.55.82) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.2562.37; Tue, 5 May 2026 13:20:26 -0700 ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=kSvavY5l67+NsIARsczFgYR0Um6UDG76ae2JKsC+dGCsY7vx1jZoOdEuEX3HW5zxjNELtjOW0LsgfZkvqBKm7oDQJUziikzoQ1YZforeChjk4831x9U32krgGUwXStzovH1YTn7xc98cZOuKQWYLqglVbwyfwDkRR9VnIjXcp3cZUmjvV6XfhIzAqTdeI5IT/vMoFemAFIV8y0ODbW/XjEknw3ZGaX1tu+9XaZJgHPpoizrWrqm4s812wYXJGg2x5kW6WZK+K5Zpdo0tJwWIfZNf4zb5kDvaWyIeFu1Fr34M2D0ErWZUKoEhnO9bGeEfceQc9nBoTNU2hnvWd/zjGg== 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=RqP/etolVFz6BCfY8P5u1QVVECWxi+PEzjbTQ9QL3gY=; b=Da0zv/r7Pbszq0PZRXREaoF4b754I2Mv61j/pVx3iarsalfHw+Iau99aVylIEcwsSvu4DeocqnzcuH5Vh20UMf9IloeaEByXzz0RMt5MU+7V4ZcDexeq+6BWwzqh1TdFROnNBQf49RDU1jJIm7UBxw+0nRxKxuGvj+bdWniMua0PdcKHDPaykavHqdW55BUamSlG6yVy0Vdc+Cib1v8waWuP5FB2Nk9rYhYRWZkwkyp5owHIBtxd4t/2alXoDG8FXBz/SwKD7LsA0cCXwdf8hCxH86RAktxNPbI7ePuBsqDtXNimUf8WcdwsB4k+edVbm8Ct/okf7/cf8SLAeVMBnA== 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 BL0PR11MB3282.namprd11.prod.outlook.com (2603:10b6:208:6a::32) by CH3PR11MB7347.namprd11.prod.outlook.com (2603:10b6:610:14f::20) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9870.25; Tue, 5 May 2026 20:20:24 +0000 Received: from BL0PR11MB3282.namprd11.prod.outlook.com ([fe80::5050:537c:f8b:6a19]) by BL0PR11MB3282.namprd11.prod.outlook.com ([fe80::5050:537c:f8b:6a19%4]) with mapi id 15.20.9870.023; Tue, 5 May 2026 20:20:24 +0000 Date: Tue, 5 May 2026 22:20:15 +0200 From: Maciej Wieczor-Retman To: Andrew Cooper CC: Xin Li , David Woodhouse , , , , "Saenz Julienne, Nicolas" , , , , , , , , , , , , , , Subject: Re: [PATCH v9 00/22] Enable FRED with KVM VMX Message-ID: References: <20251026201911.505204-1-xin@zytor.com> <7f93eb25874ddd13a1ad6e3c75785f11041c8b7f.camel@infradead.org> Content-Type: text/plain; charset="utf-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: X-ClientProxiedBy: DUZPR01CA0294.eurprd01.prod.exchangelabs.com (2603:10a6:10:4b7::13) To BL0PR11MB3282.namprd11.prod.outlook.com (2603:10b6:208:6a::32) Precedence: bulk X-Mailing-List: linux-doc@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: BL0PR11MB3282:EE_|CH3PR11MB7347:EE_ X-MS-Office365-Filtering-Correlation-Id: e9a199d9-7acf-467c-dd41-08deaae3bced 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|1800799024|376014|7416014|366016|22082099003|18002099003|56012099003; X-Microsoft-Antispam-Message-Info: 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 X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:BL0PR11MB3282.namprd11.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(7416014)(366016)(22082099003)(18002099003)(56012099003);DIR:OUT;SFP:1101; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?ZlVBVmp5RDJIZXhGUjVsNTRlK3BPcWJ2dGZBQ3RTcG5PQTJLQ28xRkxJTC9N?= =?utf-8?B?UnRsZnJGd2ZqZnl6MlVBWGxtQ0lKWVdBQ0gxc1pFWEpWRTVQbEtiOHVDZ1Zl?= =?utf-8?B?USs2U1JMS0hmaFpVeS8yelFwVWkrNlp2N1AvNkU1bE1XWXM2S0ErNEVMb2E2?= =?utf-8?B?NWpTNndCeGVjdWE1NmlvY3Zub1R6YlVXWm1EWXFaV0lDQU9GTGtIUStUZDMx?= =?utf-8?B?R0ZYelZGNmliVVRiVTYrYXdUdkVYTVcyYWIzMGEyY1IxVmNMSm9Ma1U4R1lO?= =?utf-8?B?TnRDZVI5d1hiMURBNzdBR083bVNTNSsycDlEbDcrSDZDOVZPeVpRSEVKQ3ZJ?= =?utf-8?B?OUQ5MDAzamhkMzd0Qy82V1RDZjROZ1d0aUxxbGVqUklWK3dnZmd3V2w2cWZW?= =?utf-8?B?UUpOOWdRSDhhTUcvcCtadXFPajZMNXNmdlpQemhrQkp0b0x6RU9WVUtoaSts?= =?utf-8?B?cEU1c3FrOFZNaTk2OUVoVnQ4aVhNS01NdEsvUnZuT1RseFhvVERML09vVGM0?= =?utf-8?B?U0lCTE4xRWI0Vm5vU3dPZDRkbVhSNnRnemhEeElDU1RQQ00wNlRkdVRnRkJO?= =?utf-8?B?YXhiaWRFQVIvbDd2K1ltTk84bHhxMFpwL0hsU0VFa0M1TEJCaTZiT3NYOC9E?= =?utf-8?B?YURnb2RVQWY1YWxSMkdMQ2EvMjFjczVwSWpHcUVpRm05VlJVRjFuaVNBbjB4?= =?utf-8?B?dGd3RUFPTHl3dzBXTzdMWnBndkJpKzdXT0gxVVJnb3V6cTV2MXdJV2t4bEJ0?= =?utf-8?B?ek51VStkTWJBVW1aOHZWdFgxUXZENDNaemNrTm5jWXFkWU1obGZvM2FhbVBU?= =?utf-8?B?S1lINXBnTUNZcEhqNml5WWNlRjVoYTRMS3JUK1hicTErNUgxVFZHeUdndmZ3?= =?utf-8?B?MGFkN2g3S0NOMjcxUEllZnpIUkp3UlY0WVJhZ3JSWnRHSWsySUVBV1l0TzBi?= =?utf-8?B?eWZXUmE4MTRuN1hyeFNxTy9sa0lOMUJzdklXUzlNek9kSWpGU2lVZnFwYjVs?= =?utf-8?B?ZnhZYTRsV2ZVUzBBZWg0NmNwaUZEV2NpdC9TeU9aYklyQXlLR0xqQ0RLVjVH?= =?utf-8?B?bDV3ZGVjMWRQNzBndlFERS9kNEdvbnMyL044ZGpCZkUvU2Z2UWFLengvVFNC?= =?utf-8?B?SkVNdWI0d2lQK0MxN09rSzV2Q3lyOFZhZytEZk5ZbCsra29YRis2QTdtTkV2?= =?utf-8?B?ZFJ0LzZiR0ZrbURxWHJxaEJYdkZSTXArSExuN3RLb05jRkthZnd6bkJVZVJp?= =?utf-8?B?YUVRLzZWdUZxS3QzbzhUeElTTjRMYUJEUTlNaUgyTnpwT3dGZzd0cHFiYXgr?= =?utf-8?B?VFUvSUE2T0xPK0xqb0c0YjhaL3IvRFl3Lzh6bXI4VlZOMkM3RFA1ZkdNSkQ1?= =?utf-8?B?SnFXZjQ4Uk43dUFSKzFvejZ4MTF2S0VCeTF2WnhyaFdEbjJqTkE5WFNSeW16?= =?utf-8?B?c1RYY094N3kwUUdiQlVURHluV1IyZUVWRDdMd1BXcjU4aEhBdm9CMVRSekNr?= =?utf-8?B?eGNsZllnVmhIVU1KTUF5MFNGS2liV3NNRm1lb2gwVm92bUVMU1NGVkFmaEVU?= =?utf-8?B?SXp2QnZOTWR6MU5xMDcvRE1CZFQ1dnBTMEx5SDRWTWlPeGpNWXgxOHpaR001?= =?utf-8?B?Q2N4Z1pZVE1KejFCTEV1djRGMlFTQmUwdnhKMk14OGhZQzFwUHVjZ2gxNXd5?= =?utf-8?B?ZXVTbEdjTVN0VXNWZExXdkNvcU1SZU05NjRBSWIyWm9pazBxYmpsOHFpd09o?= =?utf-8?B?bXE5YjNVS1RqQVROSVJiWU1IMG5jYkhpamV0WWl0eGxEU0FDT2ZaVS8zSzYr?= =?utf-8?B?UWsvbkdIUkJVNFdWYnZMSXczS05BZ3c2M0xyUnhZbEdSQS9PSW1MMnhwWHFT?= =?utf-8?B?dDdMOVEyd3REaEhzZ1ZsY1A5OEszQnAwcDM5R29WK0lVdmR5dU5ETUZiWXpM?= =?utf-8?B?bXU1bEhIbmxaUnU0cSs4anVNeklkZlFHaE1wS0tNUzZHdDMwaFBhSmtPazVU?= =?utf-8?B?Y284MVlnR3lUMER2d2VmQkIvcEcrbUhIZzlvOTI4SmNyNDlOcU90SjAxTkVy?= =?utf-8?B?b2x4Rjk4SGhYajFKd2JHZDBWTGdvVStUNmJqVlFMUTVneVN0b0lya244M3Zy?= =?utf-8?B?aWZ5TlF6RlhXU2xsakRlc1FTMHZEQUkyaUh5dlpIdWFuQ0JYc3RqNldIVjZ5?= =?utf-8?B?bktTd2ViNWtmQXpvMjNtSjY5aVhxY2J5dS9Vb1dIU2Qwdlp0QytIdWo1T3A4?= =?utf-8?B?blFzSG1USTl0L2lPREt1TGNNR25YRjlyR3VwUmk3c0VlWEJHd3M4Z3ZNMkt3?= =?utf-8?B?K3F6Y2JrUkxGWUFpZjd6VHJVc3UvdjlsR3o1N29xSnRmb3I0MkM4cng4Qk84?= =?utf-8?Q?thd3OuJlbyM/1WXBVHQdvqdw6mzXV0DNG6OVu?= X-Exchange-RoutingPolicyChecked: vgRGTO1DrnUze30+zXhyj82uPDzVnM1Rl/vsoNjkyA8useew9EqghZCVq2XxOWxDV7JXGq6gNVevwXvnsxVnfqHZPJeuWUqq5w0GtUuyx8+MdPV4E4VJqovxY7gWvs1pzFQc7lHveqhhrm4tiooSi3U7vZaenSPWrqyjvsDopr3+uZJvRkI7t/oZnJmVUlgoQUwLCZBu5+VaDKOWeLzqZ0+zonBcgLjiy2h49Ti9qhAGy2+JOj3gCRFlxkG4LgTSzTMtAoHQHC2swHUz5tm4ZqkwhTlK5Wo7xRXCThEt62LrTQlTaJqpuXr58Avlo6OSLG/kniTDJ/eevtsWdGfBWQ== X-MS-Exchange-CrossTenant-Network-Message-Id: e9a199d9-7acf-467c-dd41-08deaae3bced X-MS-Exchange-CrossTenant-AuthSource: BL0PR11MB3282.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 05 May 2026 20:20:24.1046 (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: 4dlR5FVAxIxZqvrcmsC3WAuamFSkOu27Rd8GQrjbm2c17X38PNtKQlw3xZxoP9NPkmGjYMTjT6za9CYFpQs95rgxRKPgGTZ0k18sZ8cTtDU= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR11MB7347 X-OriginatorOrg: intel.com On 2026-05-05 at 19:30:21 +0100, Andrew Cooper wrote: >On 05/05/2026 7:04 pm, Maciej Wieczor-Retman wrote: >> Hello! >> >> >> On 2026-04-23 at 15:56:54 -0700, Xin Li wrote: >>>> On Apr 23, 2026, at 7:35 AM, David Woodhouse wrote: >>>> Here's one to get you started (untested as I haven't found suitable >>>> hardware to test it on). >>> Same here for me now :( >> I ran David's selftest on a PTL laptop and ran into a couple of issues. >> >> ... >>>> + >>>> + /* Test 1: ICEBP (INT1) — should be EVENT_TYPE_PRIV_SWEXC (5) */ >>>> + fred_handler_called = false; >>>> + asm volatile("lea 1f(%%rip), %0\n\t" >>>> + ".byte 0xf1\n\t" >>>> + "1:" : "=r"(expected_rip) :: "memory"); >>>> + check_fred_event(expected_rip, DB_VECTOR, EVENT_TYPE_PRIV_SWEXC, >>>> + "ICEBP"); >>>> + GUEST_SYNC(0); >> The above event type test seems to fail and return 0x3 instead of 0x5: >> >> Random seed: 0x6b8b4567 >> Testing FRED event types with EPT fault on stack >> ==== Test Assertion Failure ==== >> x86/int1_fred_test.c:120: event_type == expected_type >> pid=16646 tid=16646 errno=4 - Interrupted system call >> 1 0x0000000000413349: assert_on_unhandled_exception at processor.c:659 >> 2 0x0000000000407d36: _vcpu_run at kvm_util.c:1703 >> 3 (inlined by) vcpu_run at kvm_util.c:1714 >> 4 0x0000000000403104: main at int1_fred_test.c:207 >> 5 0x00007ff8d4c2a1c9: ?? ??:0 >> 6 0x00007ff8d4c2a28a: ?? ??:0 >> 7 0x0000000000403314: _start at ??:? >> 0x3 != 0x5 (event_type != expected_type) >> >> after a little digging I think the issue could be this in arch/x86/kvm/x86.h: >> >> static inline bool kvm_exception_is_soft(unsigned int nr) >> { >> return (nr == BP_VECTOR) || (nr == OF_VECTOR); >> } >> >> Since ICEBP(INT1) results in a DB_VECTOR it's not take into account and the >> check fails. Then in vmx_inject_exception() INTR_TYPE_HARD_EXCEPTION is picked >> which is 0x3 when decoded. > >That's a real bug then. > >> I think you'd need to add another check in vmx_inject_exception() to handle that >> DB_VECTOR too. Simply changing the event type if the vector is of DB_VECTOR type >> fixes that problem but then the selftest fails in other places (assert >> fred_handler_called and saved rip vs expected_rip). I didn't yet have the time >> to figure out what could be wrong there, maybe you would have more of an idea :) > >#DB is intercepted to mitigate CVE-2015-8104 (systemwide DoS).  But, to >start with, check that the test passes when #DB is not intercepted.  >That's the basecase for architectural behaviour. I take it you mean dropping the ICEBP selftest test case and just checking INT3 and INT $0x20? In that case the other two tests pass after a minor change - namely in guest_code() the expected_rip needs to be volatile as well. Otherwise there is a RIP mismatch. Or did you mean I should check something else? >When #DB is intercepted, the type in EXIT_INTR_INFO needs preserving and >forwarding into ENTRY_INTR_INFO, because that is what distinguishes an >ICEBP #DB from other #DBs.  There's no way of recovering this detail >after the fact. > >On the injection side, some #DB's are traps and some are faults.  ICEBP >will have a fault-like VMExit but need trap semantics, so like other >soft interrupts, need INSN_LEN adding to %rip.  But, type=3 #DBs need to >leave %rip unchanged. > >~Andrew -- Kind regards Maciej Wieczór-Retman