KVM: x86: Add KVM_GET/SET_VCPU_EVENTS
This new IOCTL exports all yet user-invisible states related to
exceptions, interrupts, and NMIs. Together with appropriate user space
changes, this fixes sporadic problems of vmsave/restore, live migration
and system reset.
[avi: future-proof abi by adding a flags field]
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 34b700f..3de0b37 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2499,6 +2499,26 @@
!(svm->vcpu.arch.hflags & HF_NMI_MASK);
}
+static bool svm_get_nmi_mask(struct kvm_vcpu *vcpu)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+
+ return !!(svm->vcpu.arch.hflags & HF_NMI_MASK);
+}
+
+static void svm_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
+{
+ struct vcpu_svm *svm = to_svm(vcpu);
+
+ if (masked) {
+ svm->vcpu.arch.hflags |= HF_NMI_MASK;
+ svm->vmcb->control.intercept |= (1UL << INTERCEPT_IRET);
+ } else {
+ svm->vcpu.arch.hflags &= ~HF_NMI_MASK;
+ svm->vmcb->control.intercept &= ~(1UL << INTERCEPT_IRET);
+ }
+}
+
static int svm_interrupt_allowed(struct kvm_vcpu *vcpu)
{
struct vcpu_svm *svm = to_svm(vcpu);
@@ -2946,6 +2966,8 @@
.queue_exception = svm_queue_exception,
.interrupt_allowed = svm_interrupt_allowed,
.nmi_allowed = svm_nmi_allowed,
+ .get_nmi_mask = svm_get_nmi_mask,
+ .set_nmi_mask = svm_set_nmi_mask,
.enable_nmi_window = enable_nmi_window,
.enable_irq_window = enable_irq_window,
.update_cr8_intercept = update_cr8_intercept,
diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 22fcd27..778f059 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2639,6 +2639,34 @@
GUEST_INTR_STATE_NMI));
}
+static bool vmx_get_nmi_mask(struct kvm_vcpu *vcpu)
+{
+ if (!cpu_has_virtual_nmis())
+ return to_vmx(vcpu)->soft_vnmi_blocked;
+ else
+ return !!(vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
+ GUEST_INTR_STATE_NMI);
+}
+
+static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked)
+{
+ struct vcpu_vmx *vmx = to_vmx(vcpu);
+
+ if (!cpu_has_virtual_nmis()) {
+ if (vmx->soft_vnmi_blocked != masked) {
+ vmx->soft_vnmi_blocked = masked;
+ vmx->vnmi_blocked_time = 0;
+ }
+ } else {
+ if (masked)
+ vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
+ GUEST_INTR_STATE_NMI);
+ else
+ vmcs_clear_bits(GUEST_INTERRUPTIBILITY_INFO,
+ GUEST_INTR_STATE_NMI);
+ }
+}
+
static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu)
{
return (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) &&
@@ -3985,6 +4013,8 @@
.queue_exception = vmx_queue_exception,
.interrupt_allowed = vmx_interrupt_allowed,
.nmi_allowed = vmx_nmi_allowed,
+ .get_nmi_mask = vmx_get_nmi_mask,
+ .set_nmi_mask = vmx_set_nmi_mask,
.enable_nmi_window = enable_nmi_window,
.enable_irq_window = enable_irq_window,
.update_cr8_intercept = update_cr8_intercept,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ba8958d..35eea30 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -1342,6 +1342,7 @@
case KVM_CAP_SET_IDENTITY_MAP_ADDR:
case KVM_CAP_XEN_HVM:
case KVM_CAP_ADJUST_CLOCK:
+ case KVM_CAP_VCPU_EVENTS:
r = 1;
break;
case KVM_CAP_COALESCED_MMIO:
@@ -1883,6 +1884,61 @@
return 0;
}
+static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ vcpu_load(vcpu);
+
+ events->exception.injected = vcpu->arch.exception.pending;
+ events->exception.nr = vcpu->arch.exception.nr;
+ events->exception.has_error_code = vcpu->arch.exception.has_error_code;
+ events->exception.error_code = vcpu->arch.exception.error_code;
+
+ events->interrupt.injected = vcpu->arch.interrupt.pending;
+ events->interrupt.nr = vcpu->arch.interrupt.nr;
+ events->interrupt.soft = vcpu->arch.interrupt.soft;
+
+ events->nmi.injected = vcpu->arch.nmi_injected;
+ events->nmi.pending = vcpu->arch.nmi_pending;
+ events->nmi.masked = kvm_x86_ops->get_nmi_mask(vcpu);
+
+ events->sipi_vector = vcpu->arch.sipi_vector;
+
+ events->flags = 0;
+
+ vcpu_put(vcpu);
+}
+
+static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
+ struct kvm_vcpu_events *events)
+{
+ if (events->flags)
+ return -EINVAL;
+
+ vcpu_load(vcpu);
+
+ vcpu->arch.exception.pending = events->exception.injected;
+ vcpu->arch.exception.nr = events->exception.nr;
+ vcpu->arch.exception.has_error_code = events->exception.has_error_code;
+ vcpu->arch.exception.error_code = events->exception.error_code;
+
+ vcpu->arch.interrupt.pending = events->interrupt.injected;
+ vcpu->arch.interrupt.nr = events->interrupt.nr;
+ vcpu->arch.interrupt.soft = events->interrupt.soft;
+ if (vcpu->arch.interrupt.pending && irqchip_in_kernel(vcpu->kvm))
+ kvm_pic_clear_isr_ack(vcpu->kvm);
+
+ vcpu->arch.nmi_injected = events->nmi.injected;
+ vcpu->arch.nmi_pending = events->nmi.pending;
+ kvm_x86_ops->set_nmi_mask(vcpu, events->nmi.masked);
+
+ vcpu->arch.sipi_vector = events->sipi_vector;
+
+ vcpu_put(vcpu);
+
+ return 0;
+}
+
long kvm_arch_vcpu_ioctl(struct file *filp,
unsigned int ioctl, unsigned long arg)
{
@@ -2040,6 +2096,27 @@
r = kvm_vcpu_ioctl_x86_set_mce(vcpu, &mce);
break;
}
+ case KVM_GET_VCPU_EVENTS: {
+ struct kvm_vcpu_events events;
+
+ kvm_vcpu_ioctl_x86_get_vcpu_events(vcpu, &events);
+
+ r = -EFAULT;
+ if (copy_to_user(argp, &events, sizeof(struct kvm_vcpu_events)))
+ break;
+ r = 0;
+ break;
+ }
+ case KVM_SET_VCPU_EVENTS: {
+ struct kvm_vcpu_events events;
+
+ r = -EFAULT;
+ if (copy_from_user(&events, argp, sizeof(struct kvm_vcpu_events)))
+ break;
+
+ r = kvm_vcpu_ioctl_x86_set_vcpu_events(vcpu, &events);
+ break;
+ }
default:
r = -EINVAL;
}
