Microsoft Specific

Activates virtual machine extensions (VMX) operation in the processor.


unsigned char __vmx_on(
   unsigned __int64 *VmsSupportPhysicalAddress


[in] A pointer to a 64-bit physical address that points to a virtual-machine control structure (VMCS).

Return Value

Value Meaning
0 The operation succeeded.
1 The operation failed with extended status available in the VM-instruction error field of the current VMCS.
2 The operation failed without status available.


The __vmx_on function corresponds to the VMXON machine instruction. This function supports the interaction of a host's virtual machine monitor with a guest operating system and its applications. For more information, search for the document, "Intel Virtualization Technical Specification for the IA-32 Intel Architecture," document number C97063-002, at the Intel Corporation site.


Intrinsic Architecture
__vmx_on x64

Header file <intrin.h>

END Microsoft Specific

See also

Compiler Intrinsics