KVM: VMX: Add PAT support for EPT

GUEST_PAT support is a new feature introduced by Intel Core i7 architecture.
With this, cpu would save/load guest and host PAT automatically, for EPT memory
type in guest depends on MSR_IA32_CR_PAT.

Also add save/restore for MSR_IA32_CR_PAT.

Signed-off-by: Sheng Yang <sheng@linux.intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>

arch/x86/kvm/x86.c

@@ -452,7 +452,7 @@ static u32 msrs_to_save[] = {
 	MSR_CSTAR, MSR_KERNEL_GS_BASE, MSR_SYSCALL_MASK, MSR_LSTAR,
 #endif
 	MSR_IA32_TIME_STAMP_COUNTER, MSR_KVM_SYSTEM_TIME, MSR_KVM_WALL_CLOCK,
-	MSR_IA32_PERF_STATUS,
+	MSR_IA32_PERF_STATUS, MSR_IA32_CR_PAT
 };
 
 static unsigned num_msrs_to_save;