KVM: cleanup the failure path of KVM_CREATE_IRQCHIP ioctrl

If we fail to init ioapic device or the fail to setup the default irq
routing, the device register by kvm_create_pic() and kvm_ioapic_init()
remain unregister. This patch fixed to do this.

Signed-off-by: Wei Yongjun <yjwei@cn.fujitsu.com>
Signed-off-by: Avi Kivity <avi@redhat.com>
diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
index d5753a75..a3711f9 100644
--- a/arch/x86/kvm/i8259.c
+++ b/arch/x86/kvm/i8259.c
@@ -543,3 +543,14 @@
 
 	return s;
 }
+
+void kvm_destroy_pic(struct kvm *kvm)
+{
+	struct kvm_pic *vpic = kvm->arch.vpic;
+
+	if (vpic) {
+		kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS, &vpic->dev);
+		kvm->arch.vpic = NULL;
+		kfree(vpic);
+	}
+}
diff --git a/arch/x86/kvm/irq.h b/arch/x86/kvm/irq.h
index be399e2..0b71d48 100644
--- a/arch/x86/kvm/irq.h
+++ b/arch/x86/kvm/irq.h
@@ -75,6 +75,7 @@
 };
 
 struct kvm_pic *kvm_create_pic(struct kvm *kvm);
+void kvm_destroy_pic(struct kvm *kvm);
 int kvm_pic_read_irq(struct kvm *kvm);
 void kvm_pic_update_irq(struct kvm_pic *s);
 void kvm_pic_clear_isr_ack(struct kvm *kvm);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index bd3161c..b2f91b9 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -2771,6 +2771,8 @@
 		if (vpic) {
 			r = kvm_ioapic_init(kvm);
 			if (r) {
+				kvm_io_bus_unregister_dev(kvm, KVM_PIO_BUS,
+							  &vpic->dev);
 				kfree(vpic);
 				goto create_irqchip_unlock;
 			}
@@ -2782,10 +2784,8 @@
 		r = kvm_setup_default_irq_routing(kvm);
 		if (r) {
 			mutex_lock(&kvm->irq_lock);
-			kfree(kvm->arch.vpic);
-			kfree(kvm->arch.vioapic);
-			kvm->arch.vpic = NULL;
-			kvm->arch.vioapic = NULL;
+			kvm_ioapic_destroy(kvm);
+			kvm_destroy_pic(kvm);
 			mutex_unlock(&kvm->irq_lock);
 		}
 	create_irqchip_unlock: