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| author | Chao Peng <chao.p.peng@linux.intel.com> | 2018-10-24 16:05:15 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2018-12-21 11:28:37 +0100 |
| commit | b08c28960f254bd246af8e30a468dfc7dd56e03b (patch) | |
| tree | 07ded28e09d131d36afc941e23fc422777f24bf2 /arch/x86/kvm | |
| parent | bf8c55d8dc094c85a3f98cd302a4dddb720dd63f (diff) | |
| download | linux-b08c28960f254bd246af8e30a468dfc7dd56e03b.tar.gz | |
KVM: x86: Set intercept for Intel PT MSRs read/write
To save performance overhead, disable intercept Intel PT MSRs read/write when Intel PT is enabled in guest. MSR_IA32_RTIT_CTL is an exception that will always be intercepted. Signed-off-by: Chao Peng <chao.p.peng@linux.intel.com> Signed-off-by: Luwei Kang <luwei.kang@intel.com> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.c | 33 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx/vmx.h | 1 |
2 files changed, 27 insertions, 7 deletions
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c index a4ec5369f25e..338c65091241 100644 --- a/arch/x86/kvm/vmx/vmx.c +++ b/arch/x86/kvm/vmx/vmx.c @@ -977,15 +977,11 @@ static void pt_guest_enter(struct vcpu_vmx *vmx) if (pt_mode == PT_MODE_SYSTEM) return; - /* Save host state before VM entry */ - rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl); - /* - * Set guest state of MSR_IA32_RTIT_CTL MSR (PT will be disabled - * on VM entry when it has been disabled in guest before). + * GUEST_IA32_RTIT_CTL is already set in the VMCS. + * Save host state before VM entry. */ - vmcs_write64(GUEST_IA32_RTIT_CTL, vmx->pt_desc.guest.ctl); - + rdmsrl(MSR_IA32_RTIT_CTL, vmx->pt_desc.host.ctl); if (vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN) { wrmsrl(MSR_IA32_RTIT_CTL, 0); pt_save_msr(&vmx->pt_desc.host, vmx->pt_desc.addr_range); @@ -1934,6 +1930,7 @@ 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_update_intercept_for_msr(vmx); break; case MSR_IA32_RTIT_STATUS: if ((pt_mode != PT_MODE_HOST_GUEST) || @@ -3567,6 +3564,28 @@ void vmx_update_msr_bitmap(struct kvm_vcpu *vcpu) vmx->msr_bitmap_mode = mode; } +void pt_update_intercept_for_msr(struct vcpu_vmx *vmx) +{ + unsigned long *msr_bitmap = vmx->vmcs01.msr_bitmap; + bool flag = !(vmx->pt_desc.guest.ctl & RTIT_CTL_TRACEEN); + 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.addr_range; i++) { + vmx_set_intercept_for_msr(msr_bitmap, + MSR_IA32_RTIT_ADDR0_A + i * 2, MSR_TYPE_RW, flag); + vmx_set_intercept_for_msr(msr_bitmap, + MSR_IA32_RTIT_ADDR0_B + i * 2, MSR_TYPE_RW, flag); + } +} + static bool vmx_get_enable_apicv(struct kvm_vcpu *vcpu) { return enable_apicv; diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h index dd3b9ab90556..20172c11d5f8 100644 --- a/arch/x86/kvm/vmx/vmx.h +++ b/arch/x86/kvm/vmx/vmx.h @@ -316,6 +316,7 @@ bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu); void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked); void vmx_set_virtual_apic_mode(struct kvm_vcpu *vcpu); struct shared_msr_entry *find_msr_entry(struct vcpu_vmx *vmx, u32 msr); +void pt_update_intercept_for_msr(struct vcpu_vmx *vmx); #define POSTED_INTR_ON 0 #define POSTED_INTR_SN 1 |