| Message ID | CACzj_yVbjtmTWaF3h9+KjNMgcW-KBfpxw8R-YkffLxuV0xhAxA@mail.gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 4108676..784a552 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -1120,6 +1120,11 @@ static inline bool nested_cpu_has_xsaves(struct vmcs12 *vmcs12) vmx_xsaves_supported(); } +static inline bool nested_cpu_has_virt_x2apic_mode(struct vmcs12 *vmcs12) +{ + return nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE); +} + static inline bool is_exception(u32 intr_info) {
When L2 is using x2apic, we can use virtualize x2apic mode to gain higher performance, especially in apicv case. This patch also introduces nested_vmx_check_apicv_controls for the nested apicv patches. Signed-off-by: Wincy Van <fanwenyi0529@gmail.com> --- arch/x86/kvm/vmx.c | 114 +++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 112 insertions(+), 2 deletions(-) return (intr_info & (INTR_INFO_INTR_TYPE_MASK | INTR_INFO_VALID_MASK)) @@ -2407,6 +2412,7 @@ static __init void nested_vmx_setup_ctls_msrs(void) nested_vmx_secondary_ctls_low = 0; nested_vmx_secondary_ctls_high &= SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES | + SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE | SECONDARY_EXEC_WBINVD_EXITING | SECONDARY_EXEC_XSAVES; @@ -4168,6 +4174,52 @@ static void __vmx_enable_intercept_for_msr(unsigned long *msr_bitmap, } } +/* + * If a msr is allowed by L0, we should check whether it is allowed by L1. + * The corresponding bit will be cleared unless both of L0 and L1 allow it. + */ +static void nested_vmx_disable_intercept_for_msr(unsigned long *msr_bitmap_l1, + unsigned long *msr_bitmap_nested, + u32 msr, int type) +{ + int f = sizeof(unsigned long); + + if (!cpu_has_vmx_msr_bitmap()) { + WARN_ON(1); + return; + } + + /* + * See Intel PRM Vol. 3, 20.6.9 (MSR-Bitmap Address). Early manuals + * have the write-low and read-high bitmap offsets the wrong way round. + * We can control MSRs 0x00000000-0x00001fff and 0xc0000000-0xc0001fff. + */ + if (msr <= 0x1fff) { + if (type & MSR_TYPE_R && + !test_bit(msr, msr_bitmap_l1 + 0x000 / f)) + /* read-low */ + __clear_bit(msr, msr_bitmap_nested + 0x000 / f); + + if (type & MSR_TYPE_W && + !test_bit(msr, msr_bitmap_l1 + 0x800 / f)) + /* write-low */ + __clear_bit(msr, msr_bitmap_nested + 0x800 / f); + + } else if ((msr >= 0xc0000000) && (msr <= 0xc0001fff)) { + msr &= 0x1fff; + if (type & MSR_TYPE_R && + !test_bit(msr, msr_bitmap_l1 + 0x400 / f)) + /* read-high */ + __clear_bit(msr, msr_bitmap_nested + 0x400 / f); + + if (type & MSR_TYPE_W && + !test_bit(msr, msr_bitmap_l1 + 0xc00 / f)) + /* write-high */ + __clear_bit(msr, msr_bitmap_nested + 0xc00 / f); + + } +} + static void vmx_disable_intercept_for_msr(u32 msr, bool longmode_only) { if (!longmode_only) @@ -8513,7 +8565,59 @@ static int nested_vmx_check_msr_bitmap_controls(struct kvm_vcpu *vcpu, static inline bool nested_vmx_merge_msr_bitmap(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) { - return false; + struct page *page; + unsigned long *msr_bitmap; + + if (!nested_cpu_has_virt_x2apic_mode(vmcs12)) + return false; + + page = nested_get_page(vcpu, vmcs12->msr_bitmap); + if (!page) { + WARN_ON(1); + return false; + } + msr_bitmap = (unsigned long *)kmap(page); + if (!msr_bitmap) { + nested_release_page_clean(page); + WARN_ON(1); + return false; + } + + if (nested_cpu_has_virt_x2apic_mode(vmcs12)) { + /* TPR is allowed */ + nested_vmx_disable_intercept_for_msr(msr_bitmap, + vmx_msr_bitmap_nested, + APIC_BASE_MSR + (APIC_TASKPRI >> 4), + MSR_TYPE_R | MSR_TYPE_W); + } else + __vmx_enable_intercept_for_msr( + vmx_msr_bitmap_nested, + APIC_BASE_MSR + (APIC_TASKPRI >> 4), + MSR_TYPE_R | MSR_TYPE_W); + kunmap(page); + nested_release_page_clean(page); + + return true; +} + +static int nested_vmx_check_apicv_controls(struct kvm_vcpu *vcpu, + struct vmcs12 *vmcs12) +{ + if (!nested_cpu_has_virt_x2apic_mode(vmcs12)) + return 0; + + /* + * If virtualize x2apic mode is enabled, + * virtualize apic access must be disabled. + */ + if (nested_cpu_has2(vmcs12, SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES)) + return -EINVAL; + + /* tpr shadow is needed by all apicv features. */ + if (!nested_cpu_has(vmcs12, CPU_BASED_TPR_SHADOW)) + return -EINVAL; + + return 0; } static int nested_vmx_check_msr_switch(struct kvm_vcpu *vcpu, @@ -8809,7 +8913,8 @@ static void prepare_vmcs02(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12) else vmcs_write64(APIC_ACCESS_ADDR, page_to_phys(vmx->nested.apic_access_page)); - } else if (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm)) { + } else if (!(nested_cpu_has_virt_x2apic_mode(vmcs12)) && + (vm_need_virtualize_apic_accesses(vmx->vcpu.kvm))) { exec_control |= SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES; kvm_vcpu_reload_apic_access_page(vcpu); @@ -9020,6 +9125,11 @@ static int nested_vmx_run(struct kvm_vcpu *vcpu, bool launch) return 1; } + if (nested_vmx_check_apicv_controls(vcpu, vmcs12)) { + nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD); + return 1; + } + if (nested_vmx_check_msr_switch_controls(vcpu, vmcs12)) { nested_vmx_failValid(vcpu, VMXERR_ENTRY_INVALID_CONTROL_FIELD); return 1; -- 1.7.1 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html