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how to know what the VMM has registered for its control fields

I'm trying to find out what does the Microsoft Hypervisor register for as its control fields.

What registers do I need to be looking at it to find this? The documentaiton is unclear as to where the registers are that control the fields. It keeps saying bitmaps .. but to what.
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New Contributor I
Your question is a bit ambiguous. What control fields are you asking about? The VMX entensions use a combination of enabling bits in rflags, some MSRs and a complex 'virtual machine control structure' (VMCS) data structure read, written and activated via special purpose vmx instructructions. I'm guessing you are asking about 'what is in the VMCS that hyper-v uses'? From within a guest context you are very unlikey to be able to find or see the address of a VMCS that hyper-V would be using, and you are unlikely to be able to execute the VMX instructions necissary to access one. Hyper-V has a functional specification that provides a lot of insight into how it works and to a point provides a software interface to probe and control its state: