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Subject[PATCH 0/2] KVM: VMX: Add Force Emulation Prefix for "emulate the next instruction"
Date
This patchset introduces a Force Emulation Prefix (ud2a; .ascii "kvm") 
for "emulate the next instruction", the codes will be executed by emulator
instead of processor, for testing purposes.

A testcase here:

#include <stdio.h>
#include <string.h>

#define HYPERVISOR_INFO 0x40000000

#define CPUID(idx, eax, ebx, ecx, edx)\
asm volatile (\
"ud2a; .ascii \"kvm\"; 1: cpuid" \
:"=b" (*ebx), "=a" (*eax),"=c" (*ecx), "=d" (*edx)\
:"0"(idx) );

void main()
{
unsigned int eax,ebx,ecx,edx;
char string[13];

CPUID(HYPERVISOR_INFO, &eax, &ebx, &ecx, &edx);
*(unsigned int *)(string+0) = ebx;
*(unsigned int *)(string+4) = ecx;
*(unsigned int *)(string+8) = edx;

string[12] = 0;
if (strncmp(string, "KVMKVMKVM\0\0\0",12) == 0)
printf("kvm guest\n");
else
printf("bare hardware\n");
}

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Andrew Cooper <andrew.cooper3@citrix.com>

Wanpeng Li (2):
KVM: VMX: Introduce handle_ud()
KVM: VMX: Add Force Emulation Prefix for "emulate the next instruction"

arch/x86/kvm/vmx.c | 38 ++++++++++++++++++++++++++++++--------
1 file changed, 30 insertions(+), 8 deletions(-)

--
2.7.4

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