drivers: hv: mshv_vtl: disable TSC_ADJUST handling for CONFIG_HYPERV_VTL_MODE#120
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hargar19 merged 1 commit intomicrosoft:product/hcl-main/6.12from Apr 2, 2026
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Pull request overview
Disables x86 TSC_ADJUST-based synchronization/adjustment logic when running in Hyper-V Virtual Trust Level (VTL) mode, avoiding conflicts with Hyper-V’s partition time restore behavior.
Changes:
- Clear
X86_FEATURE_TSC_ADJUSTduring VTL platform initialization so TSC_ADJUST-dependent logic (e.g., periodic sync checks) is skipped. - Add an explanatory comment describing why TSC_ADJUST is disabled in this mode.
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…uests running in Hyper-V. For backward compatibility, turn it off only when built with CONFIG_HYPERV_VTL_MODE. This addresses an issue where the TSC_ADJUST runtime checks would conflict with restore_partition_time handling that would adjust the global TSC value using a Hyper-V hypercall. Signed-off-by: Brian Perkins <brian.perkins@microsoft.com>
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benhillis
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TSC_ADJUST handling should not be needed for guests running in Hyper-V. For backward compatibility, turn it off only when built with CONFIG_HYPERV_VTL_MODE. This addresses an issue where the TSC_ADJUST runtime checks would conflict with restore_partition_time handling that would adjust the global TSC value using a Hyper-V hypercall. Kernel change PR: microsoft/OHCL-Linux-Kernel#120 Signed-off-by: Hardik Garg [hargar@microsoft.com](mailto:hargar@microsoft.com) Signed-off-by: Hardik Garg <hargar@microsoft.com>
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drivers: hv: mshv_vtl: TSC_ADJUST handling should not be needed for guests running in Hyper-V.
For backward compatibility, turn it off only when built with CONFIG_HYPERV_VTL_MODE. This addresses an issue where the TSC_ADJUST runtime checks would conflict with restore_partition_time handling that would adjust the global TSC value using a Hyper-V hypercall.