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charset="us-ascii" Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-Exchange-RoutingPolicyChecked: fWJ4bqsVZhYSzn48QNbI6Xu5gybSoSplcaP6UOZjqq8Vam0+Yp8KvRv+1vleOgiqbWWTujK7BiWETQUwBUYuJ4c5QqQpZf9q6QRGmbtjZDFeogZcpv3C4I9inR9k9Jr9NwY30WTUkr/16/Q9+vyGZNAR4LRhV2Gxd8RhM9FJhrCU8cVawEC2oQLKvSHmZ2G3PQqKGGcAXUzEpHmqd2sx2AQi1G8QaHpHj7szNtsdMZ5lIEGnWhQXHzApl98s9tFDa1sxFcjQRVl2IAXG8RlIrxYvL+fSg/yi3lA2MnqdSdLGisj3shcv4ZV0vC2rKySj4m4srWDIdVP5T5IOcz2c/Q== X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: SA1PR11MB8857.namprd11.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 82ad3bc2-4229-4b72-f5d3-08df14c08660 X-MS-Exchange-CrossTenant-originalarrivaltime: 17 Sep 2026 13:35:23.0358 (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: JtUWyfzd++VOyvT8sGowAyZW2W8n6hEgkXIJ4SUbQ+s27RKmwLiWPCs7x2MsKnPQA0k4NeA1/mm7N4f5oznbN12DeHk83wRJFhZW3SrT4Ic= X-MS-Exchange-Transport-CrossTenantHeadersStamped: CH3PR11MB8139 X-OriginatorOrg: intel.com > > Microcode updates can usually jump revisions. However, there is an > > erratum on Granite Rapids systems. If they "jump over" revision > > 0x1000405, they result in #MC. Avoid it. >=20 > A probably silly question. > Is it valid to downgrade microcode? Within SVN in theory it can be done In practice, unless you have very special circumstances (and check with Int= el if the exact downgrade you have in mind has been tested for downgrading)= I would very strongly recommend against doing so. It may appear to work, b= ut note that=20 A -> B -> A=20 Is NOT identical to just A (staying at A) as part of the microcode load, some microcode runs as "setup" which may cha= nge settings in the CPU (versus runtime behavior changes) -- and that setup= step is not undone as you go back to A.... which means you run A with a (p= artial or whole) setup of B.=20