| Message ID | 20190507160640.4812-14-sean.j.christopherson@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: nVMX: Optimize nested VM-Entry | expand |
On 07/05/19 18:06, Sean Christopherson wrote: > VMWRITEs to GUEST_IA32_DEBUGCTL from L1 are always intercepted, and > unlike GUEST_DR7 there is no funky logic for determining the value. > > Cc: Vitaly Kuznetsov <vkuznets@redhat.com> > Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> > --- > arch/x86/kvm/vmx/nested.c | 6 +++++- > 1 file changed, 5 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c > index 2e9f8169d40a..58717dfe82c9 100644 > --- a/arch/x86/kvm/vmx/nested.c > +++ b/arch/x86/kvm/vmx/nested.c > @@ -2194,6 +2194,11 @@ static void prepare_vmcs02_full(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12) > vmcs_write64(GUEST_PDPTR2, vmcs12->guest_pdptr2); > vmcs_write64(GUEST_PDPTR3, vmcs12->guest_pdptr3); > } > + > + if (vmx->nested.nested_run_pending && > + (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS)) > + vmcs_write64(GUEST_IA32_DEBUGCTL, > + vmcs12->guest_ia32_debugctl); > } > > if (nested_cpu_has_xsaves(vmcs12)) > @@ -2270,7 +2275,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, > if (vmx->nested.nested_run_pending && > (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS)) { > kvm_set_dr(vcpu, 7, vmcs12->guest_dr7); > - vmcs_write64(GUEST_IA32_DEBUGCTL, vmcs12->guest_ia32_debugctl); > } else { > kvm_set_dr(vcpu, 7, vcpu->arch.dr7); > vmcs_write64(GUEST_IA32_DEBUGCTL, vmx->nested.vmcs01_debugctl); > I'm passing on this one. It really gets more complicated and I'm not sure the savings are worth it. Paolo
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c index 2e9f8169d40a..58717dfe82c9 100644 --- a/arch/x86/kvm/vmx/nested.c +++ b/arch/x86/kvm/vmx/nested.c @@ -2194,6 +2194,11 @@ static void prepare_vmcs02_full(struct vcpu_vmx *vmx, struct vmcs12 *vmcs12) vmcs_write64(GUEST_PDPTR2, vmcs12->guest_pdptr2); vmcs_write64(GUEST_PDPTR3, vmcs12->guest_pdptr3); } + + if (vmx->nested.nested_run_pending && + (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS)) + vmcs_write64(GUEST_IA32_DEBUGCTL, + vmcs12->guest_ia32_debugctl); } if (nested_cpu_has_xsaves(vmcs12)) @@ -2270,7 +2275,6 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, if (vmx->nested.nested_run_pending && (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_DEBUG_CONTROLS)) { kvm_set_dr(vcpu, 7, vmcs12->guest_dr7); - vmcs_write64(GUEST_IA32_DEBUGCTL, vmcs12->guest_ia32_debugctl); } else { kvm_set_dr(vcpu, 7, vcpu->arch.dr7); vmcs_write64(GUEST_IA32_DEBUGCTL, vmx->nested.vmcs01_debugctl);
VMWRITEs to GUEST_IA32_DEBUGCTL from L1 are always intercepted, and unlike GUEST_DR7 there is no funky logic for determining the value. Cc: Vitaly Kuznetsov <vkuznets@redhat.com> Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> --- arch/x86/kvm/vmx/nested.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-)