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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?utf-8?B?N3B6TGkyVUErR3pQclZYMGRveFpDVmZEcDZIUWxOWlBDbzJON0ZsRmZFOUpI?= =?utf-8?B?ekFIc1RpMnUrTHdrT0x5ZjkrL2NjOWJmdVZibE1BeS81bEhoSmFoNlBISFZv?= =?utf-8?B?TGhuWm52RksvS3RVSndhQ3MyU2ZDR3RyK1RubTNXeE0vR3NQeEc3TnZVUzBw?= =?utf-8?B?bWMrRk5GQlBjUjFNdlU0TE1YWmpsL09lU2VIMGZrUXQ1NHNWNDZhQjVRZ3VV?= =?utf-8?B?M0ErYnBlOVhQTGU1NW1pcis1Qk9qSHZjUkJOeUF1ZHl0OW9kY3I0VTF6NGxm?= =?utf-8?B?T2NyQlhGMGExSEFsMXhCcUZtNDJLczUwRTFjeWkyWFhzdzNESUQrdWV4RUtB?= =?utf-8?B?ZGJxQURWZ3k1UE85L1EvWCs5MXpXTDRxcW5hVnpIMTVkeWNCTFp0MFlCSkY3?= =?utf-8?B?Mm5Ickc3WmtrdkE5WDBYcFFhdzZMZDYybEQ2MWxoaTlxUDNucFZ0akJPVDkx?= =?utf-8?B?MHpLQlE0dEtmNTg0R3hnc3EyanU0ZnB6aG1zbnlwRTBhWE51REIzMUFHdzZO?= =?utf-8?B?OWJXbm9FemxoQ3gyQkRVQ0ExN21LTThmQytjNWRndTM0dkk4VHVWNTB4Zk9p?= =?utf-8?B?cUhoayttaVJmVnhLMFk2cmVPS1BXME1pb2ozQ3lrM2RQR21jenVRYkQvUlRl?= =?utf-8?B?dDdpejZqNDdQQXFmYzF5RDJRcmNTaUFsQUUrRHViSGhUN3BWSkNiWloySkty?= =?utf-8?B?Wkduc1hiOFZuTUU5d2tYakU2cDM5YWNXS0ZhU0ZKRlE3UmhSN0xlM0wvb1gx?= =?utf-8?B?cWRNRkNOa1JwcGVwUld0ZE8wL1BrNWI1YVhqU20rU1VBVy9veVVwVjJ4dDN3?= =?utf-8?B?dk16ZnRXTUo2bnN0M2taU0RFNVVFVDNMbzZ2UUdFSnIxNUZBUXVlcVdDSlZE?= =?utf-8?B?c3dQNE1hc0szZ0hZT1c3OHBqK1dwWUN2aGd2elFSN3ZwM2hPTVRiZzRGQWww?= =?utf-8?B?M3lSemh1TTZZRkJRSGlMcnNLWEVNdlByS3VEVE94eVhkNTdGVlBNV1NBNXk0?= =?utf-8?B?TWZwZUlkdmovTEM3K3VEaVFZNzc2aHo3YTZuaWlvVU9sdVlBbURqbml2STBL?= =?utf-8?B?Nk1mUGY5eklPYXhYOE9kejZzVHZhZDFSYVZGaENwS3V2OW9BbXZWRXc3a2ZO?= =?utf-8?B?anZFWGpDZTB5NmdrSXYvbE1XTWhvMWlNdDA3c2lzQ3laQnJnODJlcU0xNXZy?= =?utf-8?B?eFB1TDdmeWZBSmZscC9xcE8vVit2N2wzTVZPZmRQdVcyY3ovMUxuamxJMFpl?= =?utf-8?B?NnZkaFdhNEJDNDNyeDhENmtGQlFuVm01ck9ibUw4OVY5eWl0czl6Z0pVbGR4?= =?utf-8?B?c3FpZll1OHNHOWN1YXJuVXIydnc4cGZrQ2ZNbkU1TXFzMTVUQVQ1bm5TRUJh?= =?utf-8?B?Ylc2azRoSUtQK0NQZ0dqVUdMYUVUcjZXVXZVTlpVRkFMYkJYSGpMdXd6K0Nt?= =?utf-8?B?Rkx5VHc2dUVHYVl3a29GYVVQQkhsRjRQOWNzV2RYUTBtcTM4aDhhY3h6QTlL?= =?utf-8?B?UFg2a0hobzQ0R3pZWjEzM0pXR3RwWU1Gc0h0MnZXaUsyRDU3Zkk2WWNuRmxp?= =?utf-8?B?cFVYbEdjZG12OEY5QmY5L2JpMlZGcFdNTHY0QlgvNkZwbWxoQ2Y1eWd2ZEl4?= =?utf-8?B?TjM4RXh3Z2pMeWhLdFg2ZVdpeno5bUE1eGpnczVPUzU2TVh3WE5tS20xN01i?= =?utf-8?B?cE84aVJaVWNWZTZyejArVHQ2WUZ2ZXUxakFOSU9UNlB3Q3dqcDViNDl4OVFz?= =?utf-8?Q?Z93kp+UeRG697+vHbPGIFp1bqkH/7ByY73Hva4T?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 89ed5695-29cf-4008-f8f7-08d967d5b418 X-MS-Exchange-CrossTenant-AuthSource: VI1PR04MB5600.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 25 Aug 2021 14:36:19.8375 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: f7a17af6-1c5c-4a36-aa8b-f5be247aa4ba X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: BIIvV2e6NUSvqmc3LpyBt6ggcRERZFrADwNLaMGQ5IJuhmhoG0UTZKxlX5XjPEzTFH+Q0K/5ld6FU6uVuUmDCg== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB4350 On 25.08.2021 14:12, Andrew Cooper wrote: > On 24/08/2021 14:04, Jan Beulich wrote: >> On 19.08.2021 18:26, Andrew Cooper wrote: >>> In some configurations, it is safe to not overwrite the RSB on entry to Xen. >>> Both Intel and AMD have guidelines in this area, because of the performance >>> difference it makes for native kernels. >> I don't think I've come across AMD's guidelines - would you happen to >> have a pointer? > > APM Vol2 3.2.9 "Speculation Control MSRs" > > The information about SMEP is in the final paragraph before describing > MSR_SPEC_CTRL.STIBP. Ah yes, thanks. Still need to get used to this now being in the PM rather than in one or more separate docs. I now recall reading through this. Jan