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Smith" , =?UTF-8?Q?Marek_Marczykowski-G=C3=B3recki?= , Xen-devel Subject: Re: [PATCH v2 2/2] x86/ucode: Add Kconfig option to remove microcode loading To: Alejandro Vallejo , xen-devel@lists.xenproject.org References: <20260112150259.74535-1-alejandro.garciavallejo@amd.com> <20260112150259.74535-3-alejandro.garciavallejo@amd.com> <96f4f3fe-46c4-4854-af55-d5adea07c847@citrix.com> Content-Language: en-GB From: Andrew Cooper In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-ClientProxiedBy: LO4P265CA0202.GBRP265.PROD.OUTLOOK.COM (2603:10a6:600:318::8) To CH8PR03MB8275.namprd03.prod.outlook.com (2603:10b6:610:2b9::7) MIME-Version: 1.0 X-MS-PublicTrafficType: Email X-MS-TrafficTypeDiagnostic: CH8PR03MB8275:EE_|MN2PR03MB5006:EE_ X-MS-Office365-Filtering-Correlation-Id: 2bf4d0a3-cbc7-4c62-8903-08de5214023b X-MS-Exchange-SenderADCheck: 1 X-MS-Exchange-AntiSpam-Relay: 0 X-Microsoft-Antispam: BCL:0;ARA:13230040|1800799024|376014|7416014|366016; X-Microsoft-Antispam-Message-Info: =?utf-8?B?WGo1UTB3cGtZQXltQkozYzByWWFSL0o4ODgweE9nZTRpUk5DMXRxWDZTU0pt?= =?utf-8?B?QU15cW5veERhYmVXY0ZmT3drdXgyak54bk03T2pKYytXcm4rall3UkpCeStn?= =?utf-8?B?RExYZmxibjQ0dkV1K1BPbWN0UkU5dmtRQ2I3NmlPdzI1OUwrc05MRCtoL2Zv?= =?utf-8?B?R3BkVmp3YmFBY2ZqQlg4SWswSDdRckM5SXpGNFYrSnhlekJSVFkvbklUN0pk?= =?utf-8?B?VkcvTnVZejdFdnRJM3hWZ1k4OHlYZlBwUVJ6RktpT29qZllJSXlVNFF3dlBo?= =?utf-8?B?MTBzdnliZkl0aVNtWDJyYkdDdHhWODBmYjRqNWtmV0t4V3VyVExHcW1SWWgv?= =?utf-8?B?S1JIVGpUT0IzbVdxSUcxOVBhU0JXR0FYVjZIbk03MWF5QXZKVytTQXhIc0Yy?= =?utf-8?B?RitNWklUT3J6WWR2MWdWUW80cVp6OTZNVUljMHZET0h3d1pISUsxa0cwa1N3?= =?utf-8?B?YUV2QzY2cGdyL1k1WkZZTkRWMTYxaFFSWklQODNmalYzZm9iaUFlTkFOMXhu?= =?utf-8?B?T2t0S1hmUEtNRS9yd0tPZkdKV3ZNRFdBcks1b0xyYTloaVNYM0t2WEFXV1gz?= =?utf-8?B?TXF3U2N4V0Q2dTFla2NyaFNMczBJSHQ5NzU5WTk5azF6UTUvQ3F1OFNBdXh5?= =?utf-8?B?WGZ3YW01NjFHQjlBR21CSG1ObTM3blZkWTJJSnNleW5lcVBSKzE5WU5tNWVj?= =?utf-8?B?amcvNW9rQjZLRDlEdE10azlLYS9rWmE0Q3NpajBBYVdUOWEyMGF4YWg2K3Rm?= =?utf-8?B?aDYrUUtOYnRQU24xZzM1YS9LOVpXT2dmLzg4am5NNDRSRXlxNDZ3bVBUNXlM?= =?utf-8?B?Q0NONld0ZGdEVzIza2c5dERGd3B6TmVpNk1NZUIvTFpJRW9EYmNPSmpCbldL?= =?utf-8?B?dzZJMENVWklyRTkrRmhEdFF3dk05YXBkekpXbS9pSVU0QzgvSTVvS3pnS0lZ?= =?utf-8?B?UlZDQWhyUDVUL0FuZk5vSDRJTHdsMmdBNXFPNDBFbTZRRm1zQ0FCTkxOS3VP?= =?utf-8?B?NmQxS1NEeTBmdHV4RHRpSkdVMy9GMFp0elhSV05keTQ3dzZwbW5QdkE4UGRF?= =?utf-8?B?RzJpNnY5dDNhSU1KYmI4akhSSGdXaTV6dGllRlZlMUhLVVZ4SnhnTlBUcUdH?= =?utf-8?B?U09RYzBtV2hPVmZvcXB4alRCT2lSSW55MGFqVWtwYlcrTXVnTGtyY0VhMEgy?= =?utf-8?B?RDkxa2w1OTA5SmVDSmhIMFNSSlgwN0s0SU5RVGI2cmVHblBjL25LL25jNGx1?= =?utf-8?B?c29XdUdzY0dhUnZyUHdzWTd5MUdkQ2hCOW5lL3cwRXQ1Qk9Fd2pURzJmT2Ja?= =?utf-8?B?K1pZVkkxaFR1NzB4ZG0rZ3F2WndkdUtjc200R1VKMW13b1lRdStpbWgvTmhT?= =?utf-8?B?UUNtOXQvOFNoTVZ3UUtqMEpkSTlmN2hpUCt5SGxYQWlzdWhTZ1JiSTJSZDlX?= =?utf-8?B?TUQvUHRmdVJNL3VzdDRBVHVWYUVQZDRwdElUb3lrdXFuN0xXRERWUDdEdWxI?= =?utf-8?B?VzY2Y2FMQjFyL1daR0pkWGpFbDQrRDhIWkxlT1Z5dFNYNmNoU1RqUVBaRlhL?= =?utf-8?B?S0NHdlYrMFMrU1kzY25hNHBzZHNhUWVJVDErOXBIakorK0pGNVgyV1hMajN4?= =?utf-8?B?RXVXY0hkVk8zdFZaL1RrTStsamdHWS8yekpYR1JQbVl1cWRMem9xandLcThj?= =?utf-8?B?cWNsaUpIK2JVWjc0SXNQLzVMVTl0NnJBRkxBS2V3UUNVbWo0SlVIMHpVa3BI?= =?utf-8?B?UURVaWdPQlZpTjVzTjJXdDZEVmVka0lQVE1iWmpIeXN1QmtxbUpwa1JsSGI3?= =?utf-8?B?aUNZRXpDQmFuaDhwQW1HczZCWVFodFcxUkdla2NGM3BuSUQyTFJ5ZTJpdUo1?= =?utf-8?B?MWNEaGRkUjNjd2FSQllReDZRVnpTSExzSVJPbjdYOUNvNXZvTEthazZzWS9x?= =?utf-8?Q?HBO5vR844aOT9xCoyI/SOZ+veRDNBsxA?= X-Forefront-Antispam-Report: CIP:255.255.255.255;CTRY:;LANG:en;SCL:1;SRV:;IPV:NLI;SFV:NSPM;H:CH8PR03MB8275.namprd03.prod.outlook.com;PTR:;CAT:NONE;SFS:(13230040)(1800799024)(376014)(7416014)(366016);DIR:OUT;SFP:1101; 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If you set a function pointer as > IS_ENABLED(x) ? foo : NULL, rather than ifdeffing out the compiler doesn't even > need __maybe_unused to eliminate the statics. Oh, yes.  I'd forgotten that trick when I suggested __maybe_unused.  Sorry. > > I'm adjusting as needed and creating something so that... > > custom_param_if("ucode", parse_ucode, IS_ENABLED(CONFIG_MICROCODE_LOADING)); > > ... does the right thing. I'm sure it'll have uses outside this (minor) patch to > remove a number of cmdline handlers when the feature they control isn't active. This I'm rather less sure about.  The lockdown patches are also competing for a 3rd parameter in the param() APIs. Again, I think microcode is a weird (i.e. rare) subsystem where we're only compiling out part of it.  Personally I'd leave it as you had in this patch.  It was minimally invasive. ~Andrew