vmptrst

Store Pointer to VMCS

VMPTRST m64

Stores the current VMCS pointer to memory.

Details

Stores the current VMCS pointer (from the VMCS pointer register) to a 64-bit memory location. This instruction is privileged and requires VMX root operation; it clears the memory destination with the active VMCS pointer value. The CF flag is set if an error occurs (invalid VMCS pointer state); ZF is set to indicate success or failure.

Pseudocode Operation

if (VMX_mode == ROOT && VMCS_pointer != INVALID) {
  [dest] ← VMCS_pointer_register;
  CF ← 0;
  ZF ← 0;
} else {
  CF ← 1;
  ZF ← 1;
}

Example

VMPTRST [rbp-8]

Encoding

Binary Layout
0F
+0
C7
+1
ModRM
+2
 
Format VMX
Opcode NP 0F C7 /7
Extension VMX

Operands

  • dest
    64-bit memory operand (quadword)

Reference (Intel® SDM)

Instruction Forms

Opcode Instruction Op/En 64/32-bit Mode CPUID Description
NP 0F C7 /7 VMPTRST m64 M Stores the current VMCS pointer into memory.

Description

Stores the current-VMCS pointer into a specified memory address. The operand of this instruction is always 64 bits and is always in memory.

Operation

IF (register operand) or (not in VMX operation) or (CR0.PE = 0) or (RFLAGS.VM = 1) or (IA32_EFER.LMA = 1 and CS.L = 0)
THEN #UD;
ELSIF in VMX non-root operation
THEN VMexit;
ELSIF CPL > 0
THEN #GP(0);
ELSE
64-bit in-memory destination operand := current-VMCS pointer;
VMsucceed;
FI;

Flags Affected

See the operation section and Section 33.2.

Exceptions

Protected Mode Exceptions

#GP(0) If the current privilege level is not 0. If the memory destination operand effective address is outside the CS, DS, ES, FS, or GS segment limit. If the DS, ES, FS, or GS register contains an unusable segment. If the destination operand is located in a read-only data segment or any code segment. #PF(fault-code) If a page fault occurs in accessing the memory destination operand. #SS(0) If the memory destination operand effective address is outside the SS segment limit. If the SS register contains an unusable segment. #UD If operand is a register. If not in VMX operation.

Real-Address Mode Exceptions

#UD The VMPTRST instruction is not recognized in real-address mode.

Virtual-8086 Mode Exceptions

#UD The VMPTRST instruction is not recognized in virtual-8086 mode. VMPTRST—Store Pointer to Virtual-Machine Control Structure 33-19 Vol. 3C

Compatibility Mode Exceptions

#UD The VMPTRST instruction is not recognized in compatibility mode.

64-Bit Mode Exceptions

#GP(0) If the current privilege level is not 0. If the destination operand is in the CS, DS, ES, FS, or GS segments and the memory address is in a non-canonical form. #PF(fault-code) If a page fault occurs in accessing the memory destination operand. #SS(0) If the destination operand is in the SS segment and the memory address is in a non-canonical form. #UD If operand is a register. If not in VMX operation.