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X-OriginatorOrg: amd.com X-MS-Exchange-CrossTenant-OriginalArrivalTime: 20 Jan 2026 11:22:31.6523 (UTC) X-MS-Exchange-CrossTenant-Network-Message-Id: ef982f27-128e-4869-2617-08de581633ee 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: BL6PEPF00020E60.namprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Anonymous X-MS-Exchange-CrossTenant-FromEntityHeader: HybridOnPrem X-MS-Exchange-Transport-CrossTenantHeadersStamped: DS7PR12MB6237 On Tue Jan 20, 2026 at 10:53 AM CET, Alejandro Vallejo wrote: > Bus Locks are very costly and a VM left unchecked spamming instructions t= hat > lock the memory bus (e.g: unaligned atomic CAS) makes system perf take a > nosedive. This patch is similar to BLD of VMX, but for SVM. It configures= all > VMRUNs so they automatically exit at the first encounter of a buslock eve= nt, > effectively rate-limiting them. Does this warrant an entry in the CHANGELOG? Cheers, Alejandro > > Cheers, > Alejandro > > Alejandro Vallejo (2): > x86/svm: Add infrastructure for Bus Lock Threshold > x86/svm: Intercept Bus Locks for HVM guests > > xen/arch/x86/hvm/svm/svm.c | 5 +++++ > xen/arch/x86/hvm/svm/vmcb.c | 6 ++++++ > xen/arch/x86/hvm/svm/vmcb.h | 15 +++++++++++++-- > xen/arch/x86/include/asm/hvm/svm.h | 2 ++ > xen/arch/x86/include/asm/perfc_defn.h | 2 +- > 5 files changed, 27 insertions(+), 3 deletions(-) > > > base-commit: 7b3e1b4e848d34c9a5b6634009959a7b9dd42104