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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 23 Jan 2026 11:39:52.2636 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: e373d8ee-b2f6-4036-bd6b-08de5a741f79 X-MS-Exchange-CrossTenant-Id: 3dd8961f-e488-4e60-8e11-a82d994e183d X-MS-Exchange-CrossTenant-OriginalAttributedTenantConnectingIp: TenantId=3dd8961f-e488-4e60-8e11-a82d994e183d;Ip=[165.204.84.17];Helo=[satlexmb07.amd.com] X-MS-Exchange-CrossTenant-AuthSource: SJ1PEPF00001CE3.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM6PR12MB4372 On Thu Jan 22, 2026 at 7:19 PM CET, Andrew Cooper wrote: > On 22/01/2026 5:42 pm, Alejandro Vallejo wrote: >> On Thu Jan 22, 2026 at 6:10 PM CET, Andrew Cooper wrote: >>> On 22/01/2026 4:49 pm, Alejandro Vallejo wrote: >>>> Open question unrelated to the series: Does it make sense to condition= alise the >>>> MSR handlers for non intercepted MSRs on HVM_FEP? >>> I'm not quite sure what you're asking here. >>> >>> ~Andrew >> The handlers for LSTAR and the like are dead code with !CONFIG_HVM_FEP a= s far >> as I can tell. The question I'm asking is whether there is another code = path >> that might invoke MSR handlers for non-intercepted MSRs. I can't see it,= but >> I'm not sure. >> >> If there isn't I'm considering (conditionally) getting rid of them. > > Introspection can (and HVMI does) hook them.=C2=A0 Changes to LSTAR durin= g > runtime is usually an exploit in progress. > > Nested virt also makes it far more complicated to reason about > "intercepted or not", given that there are multiple opinions merged > together. > > ~Andrew nSVM definitely would trigger those, ta. Conditionally removing nSVM is in our roadmap, and VMI is already gated on ALTP2M. I'll put this on the pile somewhere. Cheers, Alejandro