Windows Driver Kit: Hypervisor
Standard Hypervisor CPUID Leaves
When the 0x40000000 leaf is queried, the hypervisor will return the maximum hypervisor CPUID leaf number and a vendor identifier signature. The following table provides the detailed return value information.
| Leaf | Hypervisor returns |
|---|
| 0x40000000 | Hypervisor CPUID leaf range and vendor identifier signature are returned in the following registers. |
| EAX | The maximum input value for the hypervisor CPUID information, which determines the CPUID leaf range. |
| EBX | The first part of the hypervisor vendor identifier signature. |
| ECX | More of the hypervisor vendor identifier signature. |
| EDX | The final part of the hypervisor vendor identifier signature. |
If the 0x40000001 leaf is queried, the hypervisor will return a value that identifies the hypervisor interface. The following table provides the detailed return value information.
| Leaf | Hypervisor returns |
|---|
| 0x40000001 | Hypervisor vendor-neutral interface identification, which determines the semantics of leaves from 0x40000002 through 0x400000FF, is returned in the following register. |
| EAX | Hypervisor interface signature. |
| EBX | Reserved. |
| ECX | Reserved. |
| EDX | Reserved. |