From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from YT3PR01CU008.outbound.protection.outlook.com (mail-canadacentralazon11020109.outbound.protection.outlook.com [52.101.189.109]) (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 10296EEAB for ; Thu, 4 Sep 2025 17:25:11 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=fail smtp.client-ip=52.101.189.109 ARC-Seal:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757006715; cv=fail; b=Xuv+sswV2EWhHyp/MNk3lRU8t4SrrT2dadbT08fQB4su2VYJBkfsUYFSLvvYIGDu3DMoBCeJwP0kixW6G4HYjuTlHeo9kOgNdtoZvpj2uf9t9X0GQ6VmNetPFIjO5LN9F3+neUr7eW4Ym1Lc+HxjjsCh5N2VzgvlwcAlP/Akoao= ARC-Message-Signature:i=2; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757006715; c=relaxed/simple; bh=aQr9Bv6MS6Bt0IIVlZQ7H3EFSytk4rum/VutDaXK3QI=; h=Message-ID:Date:Subject:To:Cc:References:From:In-Reply-To: Content-Type:MIME-Version; b=OA+qi3K2T10eCuPOvlFyEqXtb/SYpEpIvqLsspWPZa3B0lVs+7XuM+7YCaNNpvm2PNfBzPakE7bBbhy5zugEbSKbXPUfV2TLz4M/SXX4a3AqaEgiqAog4dP7dv5nN2pAcLAVQGm6gLH0BQhV88COdmFbZi6byvhaXRErNtbXqkI= ARC-Authentication-Results:i=2; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com; spf=pass smtp.mailfrom=efficios.com; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b=cUS8ZPpt; arc=fail smtp.client-ip=52.101.189.109 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=efficios.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=efficios.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=efficios.com header.i=@efficios.com header.b="cUS8ZPpt" ARC-Seal: i=1; a=rsa-sha256; s=arcselector10001; d=microsoft.com; cv=none; b=w0hbhrVgAZ5VisGuGnwv/WEwjzwONIMu71apFF+dISSz+J5o9AaoLxMk6n1Ds/t6u/fIatk9Yn2H20T1rz6j71MgdShAftQsaU6h784AILCUONXEJntd1rwWMVKZKU8ij0PtsSQ2RDeJWYU9/+8urnj6VMLvg9vIOVaA2tUI2HCOEdV4RsJx4TnToKLR2cfdQ474RnAFwS+RJGM1f8H/0NB2d1wpDaYkOcXn74gP5kICz78agq20TT9MxOUH1u/dEATVYclyWalaCcrR9Y8OuP2AS6Sf6iZ6xxemjhncbuysHfC8LGyoVyueFziBGRZ82stensRmiwrXJqKxx9vuTA== 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=vmYFmdPQa3aWBNy4Pr2KFra229DFmxC4al7o6G38MIE=; b=dU/7/9KGqMcudbcRcLSZ2/V8GzeRd/3gRsCFAVacPumkOoT9b8WgwVCu/J+ZU4aMEJGmKX+9y0KdNVj7VOqxSXeE8IPUXcPPlPCjg7FTOw13DPEOse6fy5187sCHOdcmPu5981zLuCYuaReC9XMjFz/brnS9egRYMq+c9u6ThERaZhPGvYCMxV2bLfwQzlXWc+uYOXe5OJpPF08dyrsF4borWGXNRLqlNjFa5/UVRSVize3NZ3o4F+4mz4Co6NzQwYTo7f+dX6g41Q/KpCx2g9gPKWcr6jsKb59690uyiHgVMvBpdx86P2wj1VXiK5rplsMf5s9sBnxY2Z7Ofl+kkg== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=efficios.com; dmarc=pass action=none header.from=efficios.com; dkim=pass header.d=efficios.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=efficios.com; s=selector1; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=vmYFmdPQa3aWBNy4Pr2KFra229DFmxC4al7o6G38MIE=; b=cUS8ZPptNtQkHKDepwQOEJFaGhdnJq8a45sQjXPQqTcNAl1bryYmiOEEPwSbHnNLe38YIZ+KZlTiOrFKgUVaXditSqpbeRRQNxKSf/MIILnAcWprCbBP5cUSziPgALA5mGyXII+H7mwvZ+JUrz1PaLFCDQoWhL7VDQkZRRadpPyk2He0SCtm2CG3utGQtmgbEz3RCE6jMcuImDtswdnOkMiXyUDcAWL1ma1XH06pHKPUw/BdxOInEs1U+/CZeLqbMTi2Uv9onHq3ZSXDwkZcuZ9ihTKXKbIFOtDN9QilqBZPU9SA6TrftnJj+DsoWqSnyITRsB0gOeHRpJR/a2YinA== Authentication-Results: dkim=none (message not signed) header.d=none;dmarc=none action=none header.from=efficios.com; Received: from YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:be::5) by YT2PR01MB10828.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:d8::17) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.9094.19; Thu, 4 Sep 2025 17:25:06 +0000 Received: from YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM ([fe80::50f1:2e3f:a5dd:5b4]) by YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM ([fe80::50f1:2e3f:a5dd:5b4%3]) with mapi id 15.20.9094.016; Thu, 4 Sep 2025 17:25:06 +0000 Message-ID: Date: Thu, 4 Sep 2025 13:25:05 -0400 User-Agent: Mozilla Thunderbird Subject: Re: [patch V2 23/37] rseq: Provide and use rseq_set_uids() To: Thomas Gleixner , LKML Cc: Jens Axboe , Peter Zijlstra , "Paul E. McKenney" , Boqun Feng , Paolo Bonzini , Sean Christopherson , Wei Liu , Dexuan Cui , x86@kernel.org, Arnd Bergmann , Heiko Carstens , Christian Borntraeger , Sven Schnelle , Huacai Chen , Paul Walmsley , Palmer Dabbelt References: <20250823161326.635281786@linutronix.de> <20250823161654.741798449@linutronix.de> <878qix0wx4.ffs@tglx> <87qzwozudw.ffs@tglx> Content-Language: en-US From: Mathieu Desnoyers In-Reply-To: <87qzwozudw.ffs@tglx> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-ClientProxiedBy: YQBPR0101CA0137.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:c01:e::10) To YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM (2603:10b6:b01:be::5) 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: YT2PR01MB9175:EE_|YT2PR01MB10828:EE_ X-MS-Office365-Filtering-Correlation-Id: 3257db51-c0e1-454f-3f57-08ddebd7fdc8 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|10070799003|376014|7416014; X-Microsoft-Antispam-Message-Info: =?utf-8?B?aEU1T1VYZnpEWGZjZG53UzNPL1NlY2xZVXVxemJIN0RUQnowRDlCRTh4eUo3?= =?utf-8?B?bUttMGlQUVYwNC85dlhOVHl3TmdjNVhsenl1VWRBMVRvaTMxQTRRSmJabkJW?= =?utf-8?B?NEY2ZmYrSThuQ1dVckY4WFArM2dBdlN6bUZQTmo3K1kwNzNFcWpucHRmTWVI?= =?utf-8?B?UlVIM0hoVjFvbThYRkxvSFFQNUdaQ0JBd0c5czBqd3g2ZHBwbG5URmd4K3hX?= =?utf-8?B?M0daVUZybmZwVm8xZlVkM3ZYcHFuaHA0ZW5wUk9jVFBlcWtlSldQMXJWWGJH?= =?utf-8?B?NDVHN3IxQXk0akJjSUJvWHVJdjF4cUNQNHN3dk4vbnZmc0J4TmN4alhsKzZi?= =?utf-8?B?RXpZcFRIWWlOTlVaVExKajJ5U3YxRmJNS2RQQTZNUUh3Q1FEaUZrZnp4NVBS?= =?utf-8?B?WGpaUzZvSmJIRXArN05haEhrSG9GYlZqbkYwYkJ6ZGM2RVNxTThlZTZsdEYy?= =?utf-8?B?THZFZmVMMEtpUk9YdTFNN2lIbG1WaCt6RlB4UHp4U0Z1TURuN1Q0K2ppUVY4?= =?utf-8?B?d3UyRmVRTW9GbHhVOTJycER0Ump1aGorYkExQWhDWDdXMEVDUnFIYjNDNWg1?= =?utf-8?B?Mlk1ZlpPOHRYQzhsa2ZDUm9mTncvSldRanoyVC8rWm9FWDBRaDZ2UmhVQ05U?= =?utf-8?B?S0VQZmJxVWZXS3pMSldzVThJcmJ6RXkvaTFnQTc1MCtiNDlFdmllQXNydlQy?= =?utf-8?B?bjQweWVYVC9raFZHNjB3Kzk2a0N0Qi9iUE1HVXZyMW1XeGI4NUM3amNqbi9s?= =?utf-8?B?cHEvK1d3THk3Vlc1cWtsUFVuN2pEY2MvM0lXMVp5bzNhSXVPWFkvNkEwUTZS?= =?utf-8?B?Ky9HdGQvbnJOL0x2MEJ3SmhvY09INE9RQzNWeGRpUzg1OXAyYXluZVJpODha?= =?utf-8?B?UnMrYW1nWjhSVEVnMHV5UDAwTWRRbGd1WGVtcm5XNGN6MnZWc2hQbks0OE5p?= =?utf-8?B?d2V6bk5yZXJtTkpXR2laMk9qa3d6THVsRlNxMzc3VGdvWlhnWUZmalFZT0pX?= =?utf-8?B?NXRHdFRGclJ3TG5remg2bXlQSlNhRTJFSklFb3FJczFXZEIrS3o1bzExVzZr?= =?utf-8?B?TjFrNjV2ek5DMHhLR3IvWC9TSmNiU1BmOFRqWU00YmlWTCs1Qm02enhrSkVu?= =?utf-8?B?WVZWYUdhVC9uNDRJUHN2cmJDSDA2Vm9ma2ZRT2ZjRDZrbURoSjFCdGNvR2hI?= =?utf-8?B?L1FwWTBiaUd4ZmhLUmVaQ2lQMHNLbm40bUZJZ01GekozM2ZzVWVaOFlmMkNw?= =?utf-8?B?ZmdsMWVNRXF0NGZTbVcwbmQ1THU1eDRGVW9CTmJPVFprZDg0RVVwbFpLT3Ew?= =?utf-8?B?MUFtMncyUmFPTkNDblNoMG03SjNzZGR4bmRta05HWVFNZUxpRXZyNSszUTh1?= =?utf-8?B?bVp1M1BiVEVsYTcyR3hPUzR3RitXb2dXUGZEYUo3cXE1a3kyTUk4dXhmRzVF?= =?utf-8?B?Q3FjcndCckN4VmdlUjJYYTVLQUplUTg2QThZeTRJOFEzbW1jSE8rTklJV1hF?= =?utf-8?B?N0Y2MHU5ejd3bEs5V2h4b0hpOVVVRzczcjJNZkF4N1JGNWxrNVZzZjA1QXQ2?= =?utf-8?B?cjVjYS9QczdpVUJMZ21DeXlCNVBHbGJ6RGRrYVM0SDhaakhCRFhlM25oMGNR?= =?utf-8?B?UmF0UW5jeldrN3FTWE5BQm8zdkNVV0lobko5Nm5Zdmt4UEp3SWIwRitudnls?= =?utf-8?B?ZEx4VFo5emVvVFJFRW9FdkNqem5sQzNQbDNEMXVESWd0bE82TzJOeDBnNEhu?= =?utf-8?B?L3VLdjdoRGNwNTBrOFpJT0ZjYTJzQzZuTUhoMGc4bFBvUWtJTmNFeWd0VjJP?= =?utf-8?Q?pleBC4Dvvujl94NbreaThUSipCZYlzdOyo2y4=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(10070799003)(376014)(7416014);DIR:OUT;SFP:1102; X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?K1ZxMkNtZ2tqWklXSlVjVEdHUjZmUEk4K1JWK3A1U1daN1RtbXA5VlU1RHBI?= =?utf-8?B?VFVrZlBWSWNObGZCaGFnYi9jenNNTjJBL3dBRkdQK2tRT3M2WW5JTEhtcVhi?= =?utf-8?B?UXRhcmVVcUFyYTJlRDZNQ0NLWHJzVmg1K3I2VUNtRXVJcldqdFZKeEVxdTJ6?= =?utf-8?B?Mmx5bXgyVE9MWlJyVjRmUzZxL29DUFZ3VC9IWmM5V1ZWR0xwcWN3NUhORU1i?= =?utf-8?B?SDdyUDhmNkJIY3Y1dmlVNTJFVW1IWU5WOTVoazd6S01EbnBsU1B4V04yNnhH?= =?utf-8?B?RGh1YVlqTHJzOUg2VkZ3WHYzTkUyb2dBTTVLbkxnMWd2MWhxNWROSUdLTERx?= =?utf-8?B?emVsbldpdzRTYTk5MlAwQlZXck02eGVWWXFqU2ZSemVVVTZRSk45aFVqZU5h?= =?utf-8?B?cG5KemZvM01zTFdkMFNGVU53YytMWDJMU3R5ZERESnBXZWcyMW9rZ0FVSFdT?= =?utf-8?B?Q2VuZUFlMVNRdE1RcGN1SldQRVowb0IvTC9WOWx1VFc4OGptaW91MmpsUkJP?= =?utf-8?B?THZLd3dFcFJQUExmQk1pVlIxaFJuRk9EdUtxeGN0SjR2UmwvOUV3U28zUUh1?= =?utf-8?B?NEUvMHQvcHI4SXlvRzZ6Z2dHS0lBT2lDZC8vZWl3dmhYYU4vOG9SR1JTQytK?= =?utf-8?B?MFQwMU9iaVQzbGZaaHJ2SFJpTzF0MmkxRDhjdU1nNkJ4bG9MUDZ5QXg2NVE3?= =?utf-8?B?ZlUvNmpjbkNOMjNqN3Y2cUNmRjh0azhia1dNUFN6bjlxQkxQSC9XR2Y4N2lQ?= =?utf-8?B?dVZmbWVBbmFuR3VXNzRRUmp3dnFIaWxMblVaQ2p2VmEwcjZlUGpzS0hlTHR5?= =?utf-8?B?YmZ0TVpiMUQ2YnF0MU5oSzZ0RnhOUDIrQ2t6enhJenZ3dDNNNWcvMXVpcGNa?= =?utf-8?B?N1RLRkRQRGRQcWd5SDczRWlkRml6by96U1o5YXNyZ2czMFlwRkRRZHg0akFL?= =?utf-8?B?SkgrSkYvRjJ3WGc3c3NBRDMwR3JUeXZzaGVFcXhYZ05VZVNXZTdabEhNRzlZ?= =?utf-8?B?OC93MmpLQUR4VFY0RVYxWTAzVDVORGNpb2hvY3QxOWt6OEtGek55UTlxUi94?= =?utf-8?B?QjZucmk4Z2pwcWZZb1NZcjBwK2xtYnBDaUFBK1h6K0wyWVZOaTZ0eCtmU01v?= =?utf-8?B?Z003b1M0TDFrelRTZ2ovblRTSTd5U21DMmpDRFI0OGFhaU5BakxWZ1pKWDR4?= =?utf-8?B?Tjk0dnYyeVVMc1hKOFBBNytQT3VQM3pmbStSWmk0d2tGRFM3RlJQUHBqR0d2?= =?utf-8?B?aHExclJMejRqeGRJeVgzSmc1V24rQmZQTXNjekh0RS9DME9ReEYzM1JZanhU?= =?utf-8?B?aEtHVVNwdi93VjVyZFpzWTZiUkNaRlFvVVU2M1J2OGxPZmNvSWxRR1EzNWVW?= =?utf-8?B?UlIxaUxGeVd6Y1NCL0phTk55U0dUczhuZVpGNUZJVTF3eENhWjREYS9kR3Q1?= =?utf-8?B?K3R5eWkxZW93L1lRdjJpcEt3bzZmK3VaM3VqUThXd3h4OCswbFliTWN6dmk2?= =?utf-8?B?UUE1V3dOcktlRmFxUlRjR1ZCUVRKVWxYNzZ3a0QwdUFOeVp2QjZtMDBLUDlk?= =?utf-8?B?RVhCY3FrQzVQdHBBRzVmNUUzbXhiV1p2UnRxTCtaTWRKSS9OcDNuWjQ0Yytu?= =?utf-8?B?SHNIRDZRVHZhUmxyV2JYNnFHN3JXMnNBRHNnRDEvVWxJeGdGZXNFWUpKUS9U?= =?utf-8?B?dXFkeFgvLzdoWXFkVHBYQXFROVB5N242N0NEMlh5K3BQUytCMmNyYmVUUDZQ?= =?utf-8?B?RWFvcFhaQ0o0S3lJZjlYdHpsZW1mVlErRVpGdDNSOTR4TGpVb0RDblZ6b3Rr?= =?utf-8?B?SnlXbmJsK3NJSS84Tis3V2JzL0NaY1FQZklTanErTHpGbVFjVXJDMUxBVTUy?= =?utf-8?B?SzBJaTA4ME9uaEF2ZUZ3czY4QXp1QlFzV0lIOHBJd1RhV3dKSVdwazlmWUIz?= =?utf-8?B?M21oeEQ2c1htL1hLUFlodWlOajdNaUQvUUsvL25zUk8xRGVrTGRnMGlLT3pD?= =?utf-8?B?K1pJSGR4RmwyVDl4VnNsNDhQRVZ2UEZxK2NoMkhBSGxhUVg2UElHVFJEMG9U?= =?utf-8?B?djFoUUsrQVd3ZzlMWlRqVm9Ma0hSRDFVT0UrOUdnVTd2YTg5eWhzSXFZV29T?= =?utf-8?B?N2ZkakxWalFCYkowMFYxNGsvMXFzSkpBcHFoWlJlNExzbUEralNwTjdEL2cx?= =?utf-8?B?VEJXNTFtWEV3TVNoVWpsamUvb3EwRG93QzRyMWJxN2NCTzhPUVl6WmpQeGR6?= =?utf-8?B?dGpCYys0RHVyR3lDalpJV28zTHBBPT0=?= X-OriginatorOrg: efficios.com X-MS-Exchange-CrossTenant-Network-Message-Id: 3257db51-c0e1-454f-3f57-08ddebd7fdc8 X-MS-Exchange-CrossTenant-AuthSource: YT2PR01MB9175.CANPRD01.PROD.OUTLOOK.COM X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 04 Sep 2025 17:25:06.6751 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 4f278736-4ab6-415c-957e-1f55336bd31e X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: XETtDQ7MCZiguHg66Zt9SZkPCRuy96VrJkPeUs8w9md4falRTryOJftWOwyo5/ambPNFDilM3KpZXMs8msFWU407qhpAI9uvH/qFa3C/9Zs= X-MS-Exchange-Transport-CrossTenantHeadersStamped: YT2PR01MB10828 On 2025-09-02 12:33, Thomas Gleixner wrote: > On Tue, Sep 02 2025 at 16:08, Thomas Gleixner wrote: >> On Tue, Aug 26 2025 at 10:52, Mathieu Desnoyers wrote: >>>> + >>>> + /* Cache the new values */ >>>> + t->rseq_ids.cpu_cid = ids->cpu_cid; >>> >>> I may be missing something, but I think we're missing updates to >>> t->rseq_ids.mm_cid and we may want to keep track of t->rseq_ids.node_id >>> as well. >> >> Oops. I'm sure I had that mm_cid caching, but somehow dropped it. And >> again, no need to keep track of the node id. It's stable vs. CPU ID. > > Correcting myself. You are missing that this caches the compound value > and not only the CPU id. OK, yes. Thanks for the clarification , I indeed missed that. Mathieu -- Mathieu Desnoyers EfficiOS Inc. https://www.efficios.com