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Commit 59708670 authored by Sheng Yang's avatar Sheng Yang Committed by Marcelo Tosatti
Browse files

KVM: VMX: Trap and invalid MWAIT/MONITOR instruction 



We don't support these instructions, but guest can execute them even if the
feature('monitor') haven't been exposed in CPUID. So we would trap and inject
a #UD if guest try this way.

Cc: stable@kernel.org
Signed-off-by: default avatarSheng Yang <sheng@linux.intel.com>
Signed-off-by: default avatarAvi Kivity <avi@redhat.com>
parent 186a3e52

arch/x86/include/asm/vmx.h

+1 −0
Original line number Diff line number Diff line
@@ -251,6 +251,7 @@ enum vmcs_field { 
#define EXIT_REASON_MSR_READ            31

#define EXIT_REASON_MSR_WRITE           32

#define EXIT_REASON_MWAIT_INSTRUCTION   36

#define EXIT_REASON_MONITOR_INSTRUCTION 39

#define EXIT_REASON_PAUSE_INSTRUCTION   40

#define EXIT_REASON_MCE_DURING_VMENTRY	 41

#define EXIT_REASON_TPR_BELOW_THRESHOLD 43

arch/x86/kvm/vmx.c

+10 −0
Original line number Diff line number Diff line
@@ -1224,6 +1224,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf) 
	      CPU_BASED_USE_IO_BITMAPS |

	      CPU_BASED_MOV_DR_EXITING |

	      CPU_BASED_USE_TSC_OFFSETING |

	      CPU_BASED_MWAIT_EXITING |

	      CPU_BASED_MONITOR_EXITING |

	      CPU_BASED_INVLPG_EXITING;

	opt = CPU_BASED_TPR_SHADOW |

	      CPU_BASED_USE_MSR_BITMAPS |
@@ -3416,6 +3418,12 @@ static int handle_pause(struct kvm_vcpu *vcpu) 
	return 1;

}



static int handle_invalid_op(struct kvm_vcpu *vcpu)

{

	kvm_queue_exception(vcpu, UD_VECTOR);

	return 1;

}



/*

 * The exit handlers return 1 if the exit was handled fully and guest execution

 * may resume.  Otherwise they set the kvm_run parameter to indicate what needs
@@ -3453,6 +3461,8 @@ static int (*kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = { 
	[EXIT_REASON_EPT_VIOLATION]	      = handle_ept_violation,

	[EXIT_REASON_EPT_MISCONFIG]           = handle_ept_misconfig,

	[EXIT_REASON_PAUSE_INSTRUCTION]       = handle_pause,

	[EXIT_REASON_MWAIT_INSTRUCTION]	      = handle_invalid_op,

	[EXIT_REASON_MONITOR_INSTRUCTION]     = handle_invalid_op,

};



static const int kvm_vmx_max_exit_handlers =