[PATCH 3/3] KVM: x86: fix ready_for_interrupt reporting in split IRQ chip case

[Matt Gingell <gingell@google.com>]

This patch adds a call to kvm_arch_interrupt_allowed to ensure ready for
interrupt is reported to user space correctly. This addresses a problem
observed in QEMU when kvm->ready_for_interrupt is set but the x86
interrupt flag is clear.

Additionally, test that the APIC is ready to accept an interrupt before
reporting we are ready for injection.

Reviewed-by: Andy Honig <ahonig@google.com>
Signed-off-by: Matt Gingell <gingell@google.com>
---
 arch/x86/kvm/x86.c | 10 ++++------
 1 file changed, 4 insertions(+), 6 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index fd64dee..962003b 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5835,15 +5835,13 @@ static void post_kvm_run_save(struct kvm_vcpu *vcpu)
 	kvm_run->flags = is_smm(vcpu) ? KVM_RUN_X86_SMM : 0;
 	kvm_run->cr8 = kvm_get_cr8(vcpu);
 	kvm_run->apic_base = kvm_get_apic_base(vcpu);
-	if (!irqchip_in_kernel(vcpu->kvm))
+	if (!pic_in_kernel(vcpu->kvm))
 		kvm_run->ready_for_interrupt_injection =
 			kvm_arch_interrupt_allowed(vcpu) &&
 			!kvm_cpu_has_interrupt(vcpu) &&
-			!kvm_event_needs_reinjection(vcpu);
-	else if (!pic_in_kernel(vcpu->kvm))
-		kvm_run->ready_for_interrupt_injection =
-			kvm_apic_accept_pic_intr(vcpu) &&
-			!kvm_cpu_has_interrupt(vcpu);
+			!kvm_event_needs_reinjection(vcpu) &&
+			(!lapic_in_kernel(vcpu) ||
+			 kvm_apic_accept_pic_intr(vcpu));
 	else
 		kvm_run->ready_for_interrupt_injection = 1;
 }
-- 
2.6.0.rc2.230.g3dd15c0