KVM: nVMX: Rework interception of IRQs and NMIs
Move the check for leaving L2 on pending and intercepted IRQs or NMIs
from the *_allowed handler into a dedicated callback. Invoke this
callback at the relevant points before KVM checks if IRQs/NMIs can be
injected. The callback has the task to switch from L2 to L1 if needed
and inject the proper vmexit events.
The rework fixes L2 wakeups from HLT and provides the foundation for
preemption timer emulation.
Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a45bcac45..7382625 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5821,8 +5821,10 @@
kvm_x86_ops->update_cr8_intercept(vcpu, tpr, max_irr);
}
-static void inject_pending_event(struct kvm_vcpu *vcpu)
+static int inject_pending_event(struct kvm_vcpu *vcpu, bool req_int_win)
{
+ int r;
+
/* try to reinject previous events if any */
if (vcpu->arch.exception.pending) {
trace_kvm_inj_exception(vcpu->arch.exception.nr,
@@ -5832,17 +5834,23 @@
vcpu->arch.exception.has_error_code,
vcpu->arch.exception.error_code,
vcpu->arch.exception.reinject);
- return;
+ return 0;
}
if (vcpu->arch.nmi_injected) {
kvm_x86_ops->set_nmi(vcpu);
- return;
+ return 0;
}
if (vcpu->arch.interrupt.pending) {
kvm_x86_ops->set_irq(vcpu);
- return;
+ return 0;
+ }
+
+ if (is_guest_mode(vcpu) && kvm_x86_ops->check_nested_events) {
+ r = kvm_x86_ops->check_nested_events(vcpu, req_int_win);
+ if (r != 0)
+ return r;
}
/* try to inject new event if pending */
@@ -5859,6 +5867,7 @@
kvm_x86_ops->set_irq(vcpu);
}
}
+ return 0;
}
static void process_nmi(struct kvm_vcpu *vcpu)
@@ -5963,10 +5972,10 @@
goto out;
}
- inject_pending_event(vcpu);
-
+ if (inject_pending_event(vcpu, req_int_win) != 0)
+ req_immediate_exit = true;
/* enable NMI/IRQ window open exits if needed */
- if (vcpu->arch.nmi_pending)
+ else if (vcpu->arch.nmi_pending)
req_immediate_exit =
kvm_x86_ops->enable_nmi_window(vcpu) != 0;
else if (kvm_cpu_has_injectable_intr(vcpu) || req_int_win)
@@ -7296,6 +7305,9 @@
int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu)
{
+ if (is_guest_mode(vcpu) && kvm_x86_ops->check_nested_events)
+ kvm_x86_ops->check_nested_events(vcpu, false);
+
return (vcpu->arch.mp_state == KVM_MP_STATE_RUNNABLE &&
!vcpu->arch.apf.halted)
|| !list_empty_careful(&vcpu->async_pf.done)