vmfunc

Virtual Machine Function

VMFUNC

Invoke VM function specified in EAX.

Pseudocode Operation

FUNC_NUM ← EAX
FUNC_PARAM ← ECX
INVOKE_VMFUNCTION(FUNC_NUM, FUNC_PARAM)
VMEXIT_TO_HOST

Encoding

Binary Layout

0F

+0

01

+1

D4

+2

 

Format VMX

Opcode NP 0F 01 D4

Extension VMX

Operands

Related

More in VMX

Reference

View in Intel® 64 and IA-32 Architectures SDM ↗ Intel® SDM

Instruction Forms

Opcode	Instruction	Op/En	64/32-bit Mode	CPUID	Description
NP 0F 01 D4	VMFUNC	ZO			Invoke VM function specified in EAX.

Description

This instruction allows software in VMX non-root operation to invoke a VM function, which is processor functionality enabled and configured by software in VMX root operation. The value of EAX selects the specific VM function being invoked. The behavior of each VM function (including any additional fault checking) is specified in Section 28.5.7, “VM Functions.”

Operation

Perform functionality of the VM function specified in EAX;

Flags Affected

Depends on the VM function specified in EAX. See Section 28.5.7, “VM Functions.” Protected Mode Exceptions (not including those defined by specific VM functions) #UD If executed outside VMX non-root operation. If “enable VM functions” VM-execution control is 0. If EAX ≥ 64.

Exceptions

Real-Address Mode Exceptions

Same exceptions as in protected mode. Virtual-8086 Exceptions Same exceptions as in protected mode.

Compatibility Mode Exceptions

Same exceptions as in protected mode.

64-Bit Mode Exceptions

Same exceptions as in protected mode. VMFUNC-Invoke VM function 33-13 Vol. 3C