[patch v2 8/8] KVM: x86: Disable intercept for Intel processor trace MSRs

From: Luwei Kang
Date: Tue Oct 31 2017 - 07:49:52 EST


From: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>

Pass through Intel processor trace to guest directly.

Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
---
arch/x86/kvm/vmx.c | 13 +++++++++++++
1 file changed, 13 insertions(+)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 8f61a8d..01447e2 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -7029,6 +7029,19 @@ static __init int hardware_setup(void)
!cpu_has_vmx_intel_pt() || !cpu_has_vmx_pt_use_gpa())
pt_mode = PT_MODE_SYSTEM;

+ if (pt_mode == PT_MODE_HOST_GUEST) {
+ u32 i, eax, ebx, ecx, edx;
+
+ cpuid_count(0x14, 1, &eax, &ebx, &ecx, &edx);
+ vmx_disable_intercept_for_msr(MSR_IA32_RTIT_STATUS, false);
+ vmx_disable_intercept_for_msr(MSR_IA32_RTIT_OUTPUT_BASE, false);
+ vmx_disable_intercept_for_msr(MSR_IA32_RTIT_OUTPUT_MASK, false);
+ vmx_disable_intercept_for_msr(MSR_IA32_RTIT_CR3_MATCH, false);
+ for (i = 0; i < (eax & 0x7); i++)
+ vmx_disable_intercept_for_msr(MSR_IA32_RTIT_ADDR0_A + i,
+ false);
+ }
+
return alloc_kvm_area();

out:
--
1.8.3.1