Intel 64 and IA-32 Architectures Software Developers Manual Volume 3B, System Programming Guide Part 2

Table Of Contents
21-4 Vol. 3
VMX NON-ROOT OPERATION
MONITOR. The MONITOR instruction causes a VM exit if the “MONITOR exiting”
VM-execution control is 1.
MOV from CR3. The MOV from CR3 instruction causes a VM exit if the “CR3-
store exiting” VM-execution control is 1. Note that the first processors to support
the virtual-machine extensions supported only the 1-setting of this control.
MOV from CR8. The MOV from CR8 instruction (which can be executed only in
64-bit mode) causes a VM exit if the “CR8-store exiting” VM-execution control is
1. Note that, if this control is 0, the behavior of the MOV from CR8 instruction is
modified if the “use TPR shadow” VM-execution control is 1 (see Section 21.4).
MOV to CR0. The MOV to CR0 instruction causes a VM exit unless the value of its
source operand matches, for the position of each bit set in the CR0 guest/host
mask, the corresponding bit in the CR0 read shadow. (If every bit is clear in the
CR0 guest/host mask, MOV to CR0 cannot cause a VM exit.)
MOV to CR3. The MOV to CR3 instruction causes a VM exit unless the “CR3-load
exiting” VM-execution control is 0 or the value of its source operand is equal to
one of the CR3-target values specified in the VMCS. Note that, if the CR3-target
count in n, only the first n CR3-target values are considered; if the CR3-target
count is 0, MOV to CR3 always causes a VM exit.
Note that the first processors to support the virtual-machine extensions
supported only the 1-setting of the “CR3-load exiting” VM-execution control.
These processors always consult the CR3-target controls to determine whether
an execution of MOV to CR3 causes a VM exit.
MOV to CR4. The MOV to CR4 instruction causes a VM exit unless the value of its
source operand matches, for the position of each bit set in the CR4 guest/host
mask, the corresponding bit in the CR4 read shadow.
MOV to CR8. The MOV to CR8 instruction (which can be executed only in 64-bit
mode) causes a VM exit if the “CR8-load exiting” VM-execution control is 1. Note
that, if this control is 0, the behavior of the MOV to CR8 instruction is modified if
the “use TPR shadow” VM-execution control is 1 (see Section 21.4) and it may
cause a trap-like VM exit (see below).
MOV DR. The MOV DR instruction causes a VM exit if the “MOV-DR exiting”
VM-execution control is 1. Such VM exits represent an exception to the principles
identified in Section 21.1.1 in that they take priority over the following: general-
protection exceptions based on privilege level; and invalid-opcode exceptions
that occur because CR4.DE=1 and the instruction specified access to DR4 or DR5.
MWAIT. The MWAIT instruction causes a VM exit if the “MWAIT exiting”
VM-execution control is 1.
PAUSE. The PAUSE instruction causes a VM exit if the “PAUSE exiting”
VM-execution control is 1.
RDMSR. The RDMSR instruction causes a VM exit if any of the following are true:
The “use MSR bitmaps” VM-execution control is 0.