From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jan Kiszka Subject: [PATCH 2/3] VMX: Provide support for user space injected NMIs Date: Mon, 15 Sep 2008 18:38:57 +0200 Message-ID: <48CE8FA1.2060501@siemens.com> References: <48CE8D24.9070007@siemens.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit Cc: "Yang, Sheng" , Avi Kivity To: kvm-devel Return-path: Received: from gecko.sbs.de ([194.138.37.40]:17906 "EHLO gecko.sbs.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752902AbYIORA3 (ORCPT ); Mon, 15 Sep 2008 13:00:29 -0400 In-Reply-To: <48CE8D24.9070007@siemens.com> Sender: kvm-owner@vger.kernel.org List-ID: This patch adds the required bits to the VMX side for user space injected NMIs. As with the preexisting in-kernel irqchip support, the CPU must provide the "virtual NMI" feature for proper tracking of the NMI blocking state. Workarounds for older CPUs are still under consideration. Based on the original patch by Sheng Yang. Signed-off-by: Jan Kiszka --- arch/x86/kvm/vmx.c | 111 ++++++++++++++++++++++++++++++++++------------------- 1 file changed, 72 insertions(+), 39 deletions(-) Index: b/arch/x86/kvm/vmx.c =================================================================== --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -2358,6 +2358,7 @@ static void vmx_inject_irq(struct kvm_vc static void vmx_inject_nmi(struct kvm_vcpu *vcpu) { + ++vcpu->stat.nmi_injections; vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, INTR_TYPE_NMI_INTR | INTR_INFO_VALID_MASK | NMI_VECTOR); } @@ -2374,24 +2375,76 @@ static void kvm_do_inject_irq(struct kvm kvm_queue_interrupt(vcpu, irq); } +static void enable_irq_window(struct kvm_vcpu *vcpu) +{ + u32 cpu_based_vm_exec_control; + + cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL); + cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_INTR_PENDING; + vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); +} + +static void enable_nmi_window(struct kvm_vcpu *vcpu) +{ + u32 cpu_based_vm_exec_control; + + if (!cpu_has_virtual_nmis()) + return; + + cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL); + cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_NMI_PENDING; + vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); +} + +static void enable_intr_window(struct kvm_vcpu *vcpu) +{ + if (vcpu->arch.nmi_pending) + enable_nmi_window(vcpu); + else if (kvm_cpu_has_interrupt(vcpu)) + enable_irq_window(vcpu); +} static void do_interrupt_requests(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run) { + u32 guest_intr = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO); u32 cpu_based_vm_exec_control; - vcpu->arch.interrupt_window_open = - ((vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) && - (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & 3) == 0); - - if (vcpu->arch.interrupt_window_open && - vcpu->arch.irq_summary && !vcpu->arch.interrupt.pending) - kvm_do_inject_irq(vcpu); + vcpu->arch.nmi_window_open = + !(guest_intr & (GUEST_INTR_STATE_NMI | + GUEST_INTR_STATE_MOV_SS | + GUEST_INTR_STATE_STI)); + + if (cpu_has_virtual_nmis() && + vcpu->arch.nmi_window_open && vcpu->arch.nmi_pending) { + vcpu->arch.nmi_pending = false; + vcpu->arch.nmi_injected = true; + vmx_inject_nmi(vcpu); - if (vcpu->arch.interrupt_window_open && vcpu->arch.interrupt.pending) - vmx_inject_irq(vcpu, vcpu->arch.interrupt.nr); + vcpu->arch.interrupt_window_open = 0; + } else { + vcpu->arch.interrupt_window_open = + ((vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) && + !(guest_intr & (GUEST_INTR_STATE_MOV_SS | + GUEST_INTR_STATE_STI))); + + if (vcpu->arch.interrupt_window_open && + vcpu->arch.irq_summary && !vcpu->arch.interrupt.pending) + kvm_do_inject_irq(vcpu); + + if (vcpu->arch.interrupt_window_open && + vcpu->arch.interrupt.pending) + vmx_inject_irq(vcpu, vcpu->arch.interrupt.nr); + } cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL); + + if (cpu_has_virtual_nmis() && !vcpu->arch.nmi_window_open && + (vcpu->arch.nmi_pending || kvm_run->request_nmi_window)) + cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_NMI_PENDING; + else + cpu_based_vm_exec_control &= ~CPU_BASED_VIRTUAL_NMI_PENDING; + if (!vcpu->arch.interrupt_window_open && (vcpu->arch.irq_summary || kvm_run->request_interrupt_window)) /* @@ -2400,6 +2453,7 @@ static void do_interrupt_requests(struct cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_INTR_PENDING; else cpu_based_vm_exec_control &= ~CPU_BASED_VIRTUAL_INTR_PENDING; + vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); } @@ -2903,6 +2957,14 @@ static int handle_nmi_window(struct kvm_ vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); ++vcpu->stat.nmi_window_exits; + /* + * If the user space waits to inject a NNI, exit as soon as possible + */ + if (kvm_run->request_nmi_window && !vcpu->arch.nmi_pending) { + kvm_run->exit_reason = KVM_EXIT_NMI_WINDOW_OPEN; + return 0; + } + return 1; } @@ -3032,27 +3094,6 @@ static void update_tpr_threshold(struct vmcs_write32(TPR_THRESHOLD, (max_irr > tpr) ? tpr >> 4 : max_irr >> 4); } -static void enable_irq_window(struct kvm_vcpu *vcpu) -{ - u32 cpu_based_vm_exec_control; - - cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL); - cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_INTR_PENDING; - vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); -} - -static void enable_nmi_window(struct kvm_vcpu *vcpu) -{ - u32 cpu_based_vm_exec_control; - - if (!cpu_has_virtual_nmis()) - return; - - cpu_based_vm_exec_control = vmcs_read32(CPU_BASED_VM_EXEC_CONTROL); - cpu_based_vm_exec_control |= CPU_BASED_VIRTUAL_NMI_PENDING; - vmcs_write32(CPU_BASED_VM_EXEC_CONTROL, cpu_based_vm_exec_control); -} - static int vmx_nmi_enabled(struct kvm_vcpu *vcpu) { u32 guest_intr = vmcs_read32(GUEST_INTERRUPTIBILITY_INFO); @@ -3069,14 +3110,6 @@ static int vmx_irq_enabled(struct kvm_vc (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF)); } -static void enable_intr_window(struct kvm_vcpu *vcpu) -{ - if (vcpu->arch.nmi_pending) - enable_nmi_window(vcpu); - else if (kvm_cpu_has_interrupt(vcpu)) - enable_irq_window(vcpu); -} - static void vmx_complete_interrupts(struct vcpu_vmx *vmx) { u32 exit_intr_info; @@ -3315,7 +3348,7 @@ static void vmx_vcpu_run(struct kvm_vcpu if (vmx->rmode.irq.pending) fixup_rmode_irq(vmx); - vcpu->arch.interrupt_window_open = + vcpu->arch.interrupt_window_open = vcpu->arch.nmi_window_open = (vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) & (GUEST_INTR_STATE_STI | GUEST_INTR_STATE_MOV_SS)) == 0;