lkml.org 
[lkml]   [2017]   [Oct]   [31]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[patch v2 7/8] KVM: x86: add Intel PT msr RTIT_CTL read/write
Date
From: Chao Peng <chao.p.peng@linux.intel.com>

L1 hypervisor can't get the capability of "TraceEn can be
set in VMX operation"(IA32_VMX_MISC[14]=0) and any attempt
to set IA32_RTIT_CTL.TraceEn in VMX operation using WRMSR
will cause a general-protection exception if IA32_VMX_MISC[14]
is 0. So we need to leave out write this msr in L1 VMX
operation.

Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com>
Signed-off-by: Luwei Kang <luwei.kang@intel.com>
---
arch/x86/kvm/vmx.c | 11 +++++++++++
1 file changed, 11 insertions(+)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 091120e..8f61a8d 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -936,6 +936,7 @@ static void vmx_get_segment(struct kvm_vcpu *vcpu,
static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked);
static bool nested_vmx_is_page_fault_vmexit(struct vmcs12 *vmcs12,
u16 error_code);
+static bool vmx_pt_supported(void);

static DEFINE_PER_CPU(struct vmcs *, vmxarea);
static DEFINE_PER_CPU(struct vmcs *, current_vmcs);
@@ -3384,6 +3385,11 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
return 1;
msr_info->data = vcpu->arch.ia32_xss;
break;
+ case MSR_IA32_RTIT_CTL:
+ if (!vmx_pt_supported())
+ return 1;
+ msr_info->data = vmcs_read64(GUEST_IA32_RTIT_CTL);
+ break;
case MSR_TSC_AUX:
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
@@ -3508,6 +3514,11 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
else
clear_atomic_switch_msr(vmx, MSR_IA32_XSS);
break;
+ case MSR_IA32_RTIT_CTL:
+ if (!vmx_pt_supported() || to_vmx(vcpu)->nested.vmxon)
+ return 1;
+ vmcs_write64(GUEST_IA32_RTIT_CTL, data);
+ break;
case MSR_TSC_AUX:
if (!msr_info->host_initiated &&
!guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP))
--
1.8.3.1
\
 
 \ /
  Last update: 2017-10-31 12:50    [W:0.165 / U:1.692 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site