From fb6c8198431311027c3434d4e94ab8bc040f7aea Mon Sep 17 00:00:00 2001 From: Jim Mattson Date: Thu, 16 Mar 2017 13:53:59 -0700 Subject: [PATCH] kvm: vmx: Flush TLB when the APIC-access address changes MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Quoting from the Intel SDM, volume 3, section 28.3.3.4: Guidelines for Use of the INVEPT Instruction: If EPT was in use on a logical processor at one time with EPTP X, it is recommended that software use the INVEPT instruction with the "single-context" INVEPT type and with EPTP X in the INVEPT descriptor before a VM entry on the same logical processor that enables EPT with EPTP X and either (a) the "virtualize APIC accesses" VM-execution control was changed from 0 to 1; or (b) the value of the APIC-access address was changed. In the nested case, the burden falls on L1, unless L0 enables EPT in vmcs02 when L1 doesn't enable EPT in vmcs12. Signed-off-by: Jim Mattson Signed-off-by: Radim Krčmář --- arch/x86/kvm/vmx.c | 18 +++++++++++++++++- 1 file changed, 17 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index c66436530a93..e2f608283a5a 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4024,6 +4024,12 @@ static void vmx_flush_tlb(struct kvm_vcpu *vcpu) __vmx_flush_tlb(vcpu, to_vmx(vcpu)->vpid); } +static void vmx_flush_tlb_ept_only(struct kvm_vcpu *vcpu) +{ + if (enable_ept) + vmx_flush_tlb(vcpu); +} + static void vmx_decache_cr0_guest_bits(struct kvm_vcpu *vcpu) { ulong cr0_guest_owned_bits = vcpu->arch.cr0_guest_owned_bits; @@ -8548,6 +8554,7 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set) } else { sec_exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE; sec_exec_control |= SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES; + vmx_flush_tlb_ept_only(vcpu); } vmcs_write32(SECONDARY_VM_EXEC_CONTROL, sec_exec_control); @@ -8573,8 +8580,10 @@ static void vmx_set_apic_access_page_addr(struct kvm_vcpu *vcpu, hpa_t hpa) */ if (!is_guest_mode(vcpu) || !nested_cpu_has2(get_vmcs12(&vmx->vcpu), - SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) + SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) { vmcs_write64(APIC_ACCESS_ADDR, hpa); + vmx_flush_tlb_ept_only(vcpu); + } } static void vmx_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr) @@ -10256,6 +10265,9 @@ static int prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12, if (nested_cpu_has_ept(vmcs12)) { kvm_mmu_unload(vcpu); nested_ept_init_mmu_context(vcpu); + } else if (nested_cpu_has2(vmcs12, + SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) { + vmx_flush_tlb_ept_only(vcpu); } /* @@ -11055,6 +11067,10 @@ static void nested_vmx_vmexit(struct kvm_vcpu *vcpu, u32 exit_reason, vmx->nested.change_vmcs01_virtual_x2apic_mode = false; vmx_set_virtual_x2apic_mode(vcpu, vcpu->arch.apic_base & X2APIC_ENABLE); + } else if (!nested_cpu_has_ept(vmcs12) && + nested_cpu_has2(vmcs12, + SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) { + vmx_flush_tlb_ept_only(vcpu); } /* This is needed for same reason as it was needed in prepare_vmcs02 */