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[Bug]: Typo in VMCS bit check #313

Description

@PatrickDaG

Version

trunk/main

Host OS Type

Linux

Host OS name + version

NixOS 25.11-pre

Host Architecture

x86

Guest OS Type

Linux

Guest Architecture

x86

Guest OS name + version

No response

Component

Unspecified

What happened?

In this line

|| !(pVmcs->u32ProcCtls & VMX_EXIT_CTLS_SAVE_PREEMPT_TIMER))
the check applies to the procCtls, however, the SAVE_PREEMPT_TIMER setting is an exitCtls setting.
This thus allows nested vms to start with invalid configurations, while killing valid guests.

How can we reproduce this?

Start a nested vm with VMX preemption disabled and nmi-window exiting( The corresponding bit in procCtls) enabled. This fails with error kVmxVDiag_Vmentry_SavePreemptTimer even though it is a valid configuration.

Did you upload all of your necessary log files, screenshots, etc.?

  • Yes, I've uploaded all pertinent files to this issue.

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bugSomething isn't workingfixed in svnCommit made to SVN repo. Will be on GitHub on next SVN sync. Issue/PR staged for close.

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