[PATCH v5 10/11] KVM: x86: Set intercept for Intel PT MSRs

[Luwei Kang]

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

Disable interrcept Intel PT MSRs only when Intel PT is
enabled in guest. But MSR_IA32_RTIT_CTL will alway be
intercept.

Signed-off-by: Chao Peng <chao.p.peng@xxxxxxxxxxxxxxx>
Signed-off-by: Luwei Kang <luwei.kang@xxxxxxxxx>
---
 arch/x86/kvm/vmx.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 16943a8..0a55772 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -935,6 +935,7 @@ static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12,
 static void __always_inline vmx_disable_intercept_for_msr(unsigned long *msr_bitmap,
 							  u32 msr, int type);
 static bool vmx_pt_supported(void);
+static void pt_set_intercept_for_msr(struct vcpu_vmx *vmx, bool flag);
 
 static DEFINE_PER_CPU(struct vmcs *, vmxarea);
 static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
@@ -3713,6 +3714,7 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 			return 1;
 		vmcs_write64(GUEST_IA32_RTIT_CTL, data);
 		vmx->pt_desc.guest.ctl = data;
+		pt_set_intercept_for_msr(vmx, !(data & RTIT_CTL_TRACEEN));
 		break;
 	case MSR_IA32_RTIT_STATUS:
 		if (!vmx_pt_supported() ||
@@ -5496,6 +5498,24 @@ static void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu)
 	vmx->msr_bitmap_mode = mode;
 }
 
+static void pt_set_intercept_for_msr(struct vcpu_vmx *vmx, bool flag)
+{
+	unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap;
+	u32 i;
+
+	vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_STATUS,
+							MSR_TYPE_RW, flag);
+	vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_OUTPUT_BASE,
+							MSR_TYPE_RW, flag);
+	vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_OUTPUT_MASK,
+							MSR_TYPE_RW, flag);
+	vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_CR3_MATCH,
+							MSR_TYPE_RW, flag);
+	for (i = 0; i < vmx->pt_desc.range_cnt; i++)
+		vmx_set_intercept_for_msr(msr_bitmap, MSR_IA32_RTIT_ADDR0_A + i,
+							MSR_TYPE_RW, flag);
+}
+
 static bool vmx_get_enable_apicv(struct kvm_vcpu *vcpu)
 {
 	return enable_apicv;
-- 
1.8.3.1