diff options
Diffstat (limited to 'arch/x86/kvm')
| -rw-r--r-- | arch/x86/kvm/svm.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/vmx.c | 6 | ||||
| -rw-r--r-- | arch/x86/kvm/x86.c | 15 |
3 files changed, 27 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 6ff1faf..6807531 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -4080,6 +4080,11 @@ static bool svm_cpu_has_accelerated_tpr(void) return false; } +static bool svm_has_high_real_mode_segbase(void) +{ + return true; +} + static u64 svm_get_mt_mask(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio) { return 0; @@ -4353,6 +4358,7 @@ static struct kvm_x86_ops svm_x86_ops = { .hardware_enable = svm_hardware_enable, .hardware_disable = svm_hardware_disable, .cpu_has_accelerated_tpr = svm_cpu_has_accelerated_tpr, + .cpu_has_high_real_mode_segbase = svm_has_high_real_mode_segbase, .vcpu_create = svm_create_vcpu, .vcpu_free = svm_free_vcpu, diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 862fa8f..06a186b 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -8139,6 +8139,11 @@ static void vmx_handle_external_intr(struct kvm_vcpu *vcpu) local_irq_enable(); } +static bool vmx_has_high_real_mode_segbase(void) +{ + return enable_unrestricted_guest || emulate_invalid_guest_state; +} + static bool vmx_mpx_supported(void) { return (vmcs_config.vmexit_ctrl & VM_EXIT_CLEAR_BNDCFGS) && @@ -10296,6 +10301,7 @@ static struct kvm_x86_ops vmx_x86_ops = { .hardware_enable = hardware_enable, .hardware_disable = hardware_disable, .cpu_has_accelerated_tpr = report_flexpriority, + .cpu_has_high_real_mode_segbase = vmx_has_high_real_mode_segbase, .vcpu_create = vmx_create_vcpu, .vcpu_free = vmx_free_vcpu, diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 7489871..43f0df7 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -2900,6 +2900,17 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) #endif r = 1; break; + case KVM_CAP_X86_SMM: + /* SMBASE is usually relocated above 1M on modern chipsets, + * and SMM handlers might indeed rely on 4G segment limits, + * so do not report SMM to be available if real mode is + * emulated via vm86 mode. Still, do not go to great lengths + * to avoid userspace's usage of the feature, because it is a + * fringe case that is not enabled except via specific settings + * of the module parameters. + */ + r = kvm_x86_ops->cpu_has_high_real_mode_segbase(); + break; case KVM_CAP_COALESCED_MMIO: r = KVM_COALESCED_MMIO_PAGE_OFFSET; break; @@ -4299,6 +4310,10 @@ static void kvm_init_msr_list(void) for (i = j = 0; i < ARRAY_SIZE(emulated_msrs); i++) { switch (emulated_msrs[i]) { + case MSR_IA32_SMBASE: + if (!kvm_x86_ops->cpu_has_high_real_mode_segbase()) + continue; + break; default: break; } |
