[PATCH 13/45] KVM: VMX: Provide support for user space injected NMIs

Avi Kivity
2008-12-08T11:53:31Z

From: Jan Kiszka <jan.kiszka@siemens.com>

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.

Based on the original patch by Sheng Yang.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Sheng Yang <sheng.yang@intel.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
---
arch/x86/kvm/vmx.c | 33 +++++++++++++++++++++++++++++++++
1 files changed, 33 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 38d1385..f16a62c 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2360,6 +2360,7 @@ static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
{
struct vcpu_vmx *vmx = to_vmx(vcpu);

+ ++vcpu->stat.nmi_injections;
if (vcpu->arch.rmode.active) {
vmx->rmode.irq.pending = true;
vmx->rmode.irq.vector = NMI_VECTOR;
@@ -2428,6 +2429,30 @@ static void do_interrupt_requests(struct kvm_vcpu *vcpu,
{
vmx_update_window_states(vcpu);

+ if (cpu_has_virtual_nmis()) {
+ if (vcpu->arch.nmi_pending && !vcpu->arch.nmi_injected) {
+ if (vcpu->arch.nmi_window_open) {
+ vcpu->arch.nmi_pending = false;
+ vcpu->arch.nmi_injected = true;
+ } else {
+ enable_nmi_window(vcpu);
+ return;
+ }
+ }
+ if (vcpu->arch.nmi_injected) {
+ vmx_inject_nmi(vcpu);
+ if (vcpu->arch.nmi_pending
+ || kvm_run->request_nmi_window)
+ enable_nmi_window(vcpu);
+ else if (vcpu->arch.irq_summary
+ || kvm_run->request_interrupt_window)
+ enable_irq_window(vcpu);
+ return;
+ }
+ if (!vcpu->arch.nmi_window_open || kvm_run->request_nmi_window)
+ enable_nmi_window(vcpu);
+ }
+
if (vcpu->arch.interrupt_window_open) {
if (vcpu->arch.irq_summary && !vcpu->arch.interrupt.pending)
kvm_do_inject_irq(vcpu);
@@ -2959,6 +2984,14 @@ static int handle_nmi_window(struct kvm_vcpu *vcpu, struct kvm_run *kvm_run)
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 NMI, 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;
}

--
1.6.0.3