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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: R2WA+Y223XxCySX/5g0sDiJIYpMzSy51Z+GWkeqqyOuIYPhb+KAy5FHjHFQp9QcxDOALFvqQYrx8G6PKdgpYUF4msaIlrjdGgOyjKTFn9vDgJnqUi86RFdWx6dlu6odqN8Qi+fwClYrLcV1D4KCZiWcVrUEQIpx5DErFXklttbbjJ1eSvz99RzJ5tT3+6enOmWOZFeQHXDBjlWgBsu4ELOiOIVcxndreph1h55zyHxdaWfiptrvglbSV0S3F1/MNyRnWBeVOXvnWJmpvrlP8LH0tP0z1/IaCKjqhO2Y6Iaiv6fyQpMcCC/ToDt9/Oqi4QSFcLuiTDLapsJIQJ9+RW+l0PpKmr2v8rCyvQ/El4aNJK/MJ/ShF5ogF+Ki3LjVsplwx3x2YftIaZsoOkb1eLlG/67V0exmjdNYq5od0Ytq4ps5Sx0VuRiY24E32nxnY X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 08 Apr 2026 05:09:31.8860 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: 4279e5b8-5920-4717-e227-08de952d04c4 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=[satlexmb08.amd.com] X-MS-Exchange-CrossTenant-AuthSource: BN1PEPF0000468A.namprd05.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: PH7PR12MB9104 On 3/31/2026 11:04 PM, Sean Christopherson wrote: > On Tue, Mar 24, 2026, Manali Shukla wrote: >> The intent is purely observational — give hypervisor owners >> visibility into which guest is generating bus locks so they can act >> accordingly. No policy enforcement is done in the kernel. Suggestions >> on the approach are welcome. > > This makes no sense. KVM is exiting to userspace, the hypervisor owner doesn't > need to grep dmesg to understand *exactly* what vCPU is generating bus locks. I agree that the VMM receives KVM_EXIT_X86_BUS_LOCK and knows which vCPU caused it, and I am fine with that approach. However, this request came from a customer who wanted to know which guest is causing bus locks at which RIP in dmesg, similar to how split lock detection on Intel does it. I am trying to address that use case. -Manali