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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?yY7tjiYu0byrtui1oiY5ladOpcha4mdEzMd3hzLATzylJyv2nhcbRw1Pvz2J?= =?us-ascii?Q?AL8cwsHipHbCoIX0/J7fYdA/q4ihyJ4NtTCHkvQRU5FvhD+vv/4wbM0WhDda?= =?us-ascii?Q?jYZ7z9okkQJqGrF06WjazoBNFEmQ9ffpaIN/peeKwuTqKoyAPsa1gJXr9R2r?= =?us-ascii?Q?/gGIIjFkhZIkxbmeqM7Q7Ugh6E5DtoIB78YzBCR0nih6IDswsaMXWGQTykZz?= =?us-ascii?Q?ied3Ub57rxdi6BjD5Hr3BpusIViN+U5CyCGZMdxoCBXIqT3ZhozaX8T458GN?= =?us-ascii?Q?LuslA0lRE+BfcNt9qh9VswqF1bkx49aLC2+22BdeyYy7uF2lAQLLFcyelZ7L?= =?us-ascii?Q?8sTtlou1BK3a6spDTeq42+DI1b4UaCVWxITIYngM9Hq4LgfxFPiFJ9hsHWia?= =?us-ascii?Q?iBPABEW+LzzRtN8hWvTEKGc5jrVAjV9gb6ZgcEv9I4x5u0MpXp042h3a+2we?= =?us-ascii?Q?UTMoBxQjlgfI1mX8gN6evfsPc12SGpYwpTWd7Q6oNJgIpc8hNCgXRLuwZLDf?= =?us-ascii?Q?PZ1b8hX/t65UxvC+e8ejAa+fDwwKddqB3pqIsFmBMt1oAObd8UPiEjk2rRJA?= =?us-ascii?Q?puP1qc3AkJBU7wx3jPKvfRCmajhRLMX7xyDT3bezTjECrwXvV/VjpMHdZq55?= =?us-ascii?Q?lnk6k0ckFOyfDK6BAIJsdFtSOK/1moCDAe61JiiukKwquLp97w8XrWDL/n4w?= =?us-ascii?Q?io3wOeYVPcs41TB1sj2bxZ1MB2iaIHaQduR5Ogo7pnBwHqcKZRKC05+HIW6D?= =?us-ascii?Q?9GyehVWcinaxbxoYb47MyAxWI5QimSl8bN/XYYMrrkvKXnlqRdvB8pqiehJK?= =?us-ascii?Q?w71WMTwUNUzmEv4hZaZTQDS5Mr9Q738ea5uy60vqUx8S8pHNdqvJdA8bEKQB?= =?us-ascii?Q?V3+f9R00bhVmUoGj6LZu0lFzZK+z/I9WB1z+5hvXYOHcylB0BNAfw0AkYB+u?= =?us-ascii?Q?7rHIdeTDT5EyL6KX3Gm9Pm5CVzypJv/MkvCoEBKSGyb7fFkJjVWdrmOAhPiD?= =?us-ascii?Q?3sT06hOPZP/DVkxTu3UrtkhuuBOf6oZQhXtZGPU2wWqtc8bH/lVfPxEc1hkh?= =?us-ascii?Q?tdDg5ByJwOCfQnOwaK4rhkoZY8+vi8waTBhXwdO5dpVdKFJ39WY5cfe9qs49?= =?us-ascii?Q?zytvaUs/EgievR4lbF5MM3e9AiTY7JqgD0TDiRj/AEsIekQ4Fac/tmSNKHxx?= =?us-ascii?Q?eXwHW3CNjN5+HLupZXArD6bV5NeniwMGuXGP0+Gc4xfaPNSLbVAyw3wXUP+C?= =?us-ascii?Q?ASfCsBA7r3qpZTb9nFD+YgGfD3NtEpZyRJCmYIeeNpdNYlhsIcYMnwyoM3op?= =?us-ascii?Q?6YP6/sX5PMAoGOHLddcdPG0E9UUbO641P2B3vMpWp7VwOfH1hRtN2jcyCgNT?= =?us-ascii?Q?7vGIOrQ8gg6vBwGUHuigc9qmBFa6IEMOR6cO8s/efWmfdM5TBJODWL2a6WWa?= =?us-ascii?Q?iwlqKJzB7yTaYoCftOQJcNRFeGSm3iF/wvAl0KPfw3yeH3jMyOY7QILqRQjg?= =?us-ascii?Q?gE4Rd4KsmNmgLbWfg517jqYBFmEU+Av6BDwWnHsLljZkxQvRBTUuWCuwgoXY?= =?us-ascii?Q?21DL21wpVBJ6lqbbbZ+VQwCqkvD8/cjn+w8xkxpPhu1T0TqIzss5x3wBgDa1?= =?us-ascii?Q?vt9UZOF3ozOfpOZv1jwZVlhXp9o9T7gTP7KM+sc0UfyoZ3MYRBJpMOhmqjE+?= =?us-ascii?Q?WwkX1f+Pg+/wsUf/dUB+1Tu3XulF2d5l79o0jqe/E7Iq66HIhVoa9Xe5SMHc?= =?us-ascii?Q?NPBCaU/q+A=3D=3D?= X-OriginatorOrg: suse.com X-MS-Exchange-CrossTenant-Network-Message-Id: 552c96d8-4929-4907-78f5-08da237a2e28 X-MS-Exchange-CrossTenant-AuthSource: DU2PR04MB8616.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 21 Apr 2022 09:34:49.5295 (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: sgXlN/jkGMvat+BMYfzE62YTiBYCUHrPcSpAdhuTMQ/lHlgz+1j2gc/8O5GzBpmLKXwPW0mlgYO6gm9NMPNk6g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: VI1PR04MB3968 On 31.03.2022 11:27, Roger Pau Monne wrote: > Use the logic to set shadow SPEC_CTRL values in order to implement > support for VIRT_SPEC_CTRL (signaled by VIRT_SSBD CPUID flag) for HVM > guests. This includes using the spec_ctrl vCPU MSR variable to store > the guest set value of VIRT_SPEC_CTRL.SSBD, which will be OR'ed with > any SPEC_CTRL values being set by the guest. >=20 > On hardware having SPEC_CTRL VIRT_SPEC_CTRL will not be offered by > default to guests. VIRT_SPEC_CTRL will only be part of the max CPUID > policy so it can be enabled for compatibility purposes. >=20 > Some reasoning regarding why '!s' is used to annotate the feature: > * '!': the feature might be exposed to guests even when not present > on the host hardware. As mentioned before I don't think ! is to be used for this particular purpose. But this needs input from Andrew. Hence ... > * 's': the feature won't be exposed by default. >=20 > Suggested-by: Andrew Cooper > Signed-off-by: Roger Pau Monn=C3=A9 ... only tentatively: Reviewed-by: Jan Beulich Jan