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Date: Wed, 21 Jan 2026 18:55:49 +0100 From: Roger Pau =?utf-8?B?TW9ubsOp?= To: Jan Beulich Cc: "xen-devel@lists.xenproject.org" , Andrew Cooper Subject: Re: [PATCH v4 2/8] x86/HPET: make another channel flags update atomic Message-ID: References: <57f34114-54b7-483d-8ac0-e9fa49df959f@suse.com> <757cba5d-2c9f-40ae-8eae-6309979bbba5@suse.com> Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8bit In-Reply-To: <757cba5d-2c9f-40ae-8eae-6309979bbba5@suse.com> X-ClientProxiedBy: MR1P264CA0202.FRAP264.PROD.OUTLOOK.COM (2603:10a6:501:57::19) To CH7PR03MB7860.namprd03.prod.outlook.com (2603:10b6:610:24e::14) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH7PR03MB7860:EE_|SJ2PR03MB7500:EE_ X-MS-Office365-Filtering-Correlation-Id: 014a11d4-8280-4f90-847a-08de591651b4 X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|366016|1800799024|376014|7053199007; X-Microsoft-Antispam-Message-Info: =?utf-8?B?b0lZYWhRS2VUSDB6OU1rWEZYcjdmMFZlbVdOYzZSeW4yVWxncDBRU0xXUVZy?= =?utf-8?B?cFFXK2g1eGJRT3ExSU9iUGt1cEdGdTNvVkFkOEFqOUxxNzZRNmxrV3BaVENl?= =?utf-8?B?RjNOZG5DVE5EdGk0eGoxYmpMQ0tYblQ3NWp3WEtQTjBDTTZ1WDJGaHVYRUxE?= =?utf-8?B?eE9XVW5BUXBhOUk2UTRpQTB3SGZuekNDRndOOUM3bmRRV01DQ2psaFl5S3ht?= =?utf-8?B?NjBwWjFYalFxWUNmM2YzZzZiQ21sWkJnYUsrWXFTOVNCMy8wbzdFcUlyL1l6?= =?utf-8?B?M1hoWXhINWtaTXZ2cGlPUzRnWmhxQ2dhZXQxOXllSjFsUTdEZUppbDRUTCtH?= =?utf-8?B?c2pHWUZYQWE5RGRHb1V3TlVIcFdKV1QxZDNqemo3a1hYMTF2MS9vd25yWmda?= =?utf-8?B?c3I1WDZYTGRuM0VoOHJaRC9HNjlRYkR5VXJWeUlJZnpZRWhDTWwxTmoraXhi?= =?utf-8?B?Yk5mU1VVMHhGeElXL2VLL0xYWVRkUVB3NVltQzU4R3lBN3o5VzZSeWtycU1v?= =?utf-8?B?UGIrMVVVbElZNmpHUXkrUHdwUVdmaXQxSHZCa01FSXV3UG1MZEtUUGRGSnR3?= =?utf-8?B?MG11ZHZhUTVyVTJkam1ocmRRTUhyYTU0VzJXckRQRTRWTzl2bFN0VTZCcy9G?= =?utf-8?B?U1BVMElCY24wRHovUjVFK0o0TVlqOWpIWDF0TWF6NDlic1pFRmNCejhDZzdm?= =?utf-8?B?bzZ6R1kvaGtYY0ozcnp5TnB5bllSbXlYNS8yNTEvRTA3ai9yVHRUaFhROFRR?= =?utf-8?B?RkUzMXVYQUFNTG54YTF6bU5teThBZnJTL0VJQ3JHb2RFSVRoN0dvMUFhSW9o?= =?utf-8?B?cmg2Slk5Q3J1eXZZQnd5aEFRcUJ4SmpZMm0zNk8relZsNWtqMFc5Z0JZeFpi?= =?utf-8?B?ZXlkcER4OGo0MmhucnVZek9lVDdGRTRYREJ3SHA5OFBVc1ZmMVVUZ3JuSCtK?= =?utf-8?B?ODRUUENlanhWRW1PQXRGN0tBZjFVRTNGVDE2QWdrMzlKbWpqN3Ryb1BrVENO?= =?utf-8?B?WVB3T1F0bWtXZXRJeGZaRzBlZzVQWndocUhqRGVCUXFiTkROZ3U5WEdWSW05?= =?utf-8?B?QktlWlVQY3FUWXhQUnlzSXJybWpsTjFSczJDRXhiWis1NjJ3UTlZMU1leGRh?= =?utf-8?B?MGtUZnZDVFFpemo5YXdjR2szVE41SnZaUGhRVEgyZXFKdXRFSU5vaGhkV1NN?= =?utf-8?B?aENvVWFuNkFrY3ovd1JFWjVRL2ZsU2NqY0JPdXdPSHZycFZRWDRxU1NEOHph?= =?utf-8?B?TWpOY3c3NjdqeHEzcU1WSXJ1WHpHc2JucEoxUnpuR1NmWWpyUVYvaEp6TWtv?= =?utf-8?B?cEtzaVJ3Q2Nmclladm5WRVlNeTFoTnpJVmd6K0xDYUx1MnF1dmdKSlo1Wis4?= =?utf-8?B?b2JHR0ExL2phVTNOU1hDYTFvd2VMaU9LM0ViWTVGV1VxSld6dzFLM1Z0eWpZ?= =?utf-8?B?RFFYeDlVd2lXSko0UUxLYmFDblMraDViZTNlejF4dEdpMU1TNm9wMnFNNE5k?= =?utf-8?B?bVRGWW91b09wcExaS1dTdk8vc2ZBdjhHeS96VHRJY2lKZXd6VmlneTd2Nk1x?= =?utf-8?B?N1NhbTlWbzROazhXK1JsZnU2REEzTk8vMFJUMEFreEExRDlhd3lJQzdSMG0w?= =?utf-8?B?ZE1EOVd0VDdiVGZvYkFlanFHakpEOXdFVXJaRTVXYWJtdkZQYUFoeVMxQ2Ns?= =?utf-8?B?cXVWSldJV3JIa1c3WTFrZUo4WlBpYnFSNVEvd3VHckthb21OdjFjOEIvcVNU?= =?utf-8?B?K2Q4Ulo1aW1vcmZha1Nmb3ZRYTI2RUVYM3FQU0V0U2dtVW5LUzZxM3VWdHEz?= =?utf-8?B?bHErd2FGNzVOSFQ3RW9NMmxSaURXTXZGVG1nOFhRTUFienhoNFdFc05TRS9Y?= =?utf-8?B?emVya0NaTUdEbzVZdnVRSHpKT0lHb2hveGIyMlZYSFFTT1REYkNNR0lSRitI?= =?utf-8?B?T1JQUkgzTXhKL1JiajJBMGFkTDh2WCsyVmVjQUliN0UxSFFqUDd4dmQwOWNQ?= =?utf-8?B?N3BicHB0bHVTQkNoWisxNzExMTlwdTNRelVtQnZ0S3JoK1FqOGdqaEhncXlo?= =?utf-8?B?YzRnTTd6OVN3WlFQWS9aUTZwWFFaR1lUZDVTMXhLS3FlYjNaSXhVbm8wZzQ5?= =?utf-8?Q?QI/c=3D?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH7PR03MB7860.namprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(366016)(1800799024)(376014)(7053199007);DIR:OUT;SFP:1101; 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While possibly any such updates would > only ever occur when HPET_EVT_LEGACY isn't set in the first place, this > doesn't look straightforward to prove, so better be on the safe side. > > Fixes: d09486dba36a ("cpuidle: Enable hpet broadcast by default") > Signed-off-by: Jan Beulich I also think it's quite likely that hpet_disable_legacy_broadcast() is not possible to be used concurrently while the setting of the other flags, that seem to happen in broadcast mode only, but better be on the safe side. Acked-by: Roger Pau Monné Thanks, Roger.