KVM: Split vcpu creation to avoid vcpu_load() before preemption setup

Split kvm_arch_vcpu_create() into kvm_arch_vcpu_create() and
kvm_arch_vcpu_setup(), enabling preemption notification between the two.
This mean that we can now do vcpu_load() within kvm_arch_vcpu_setup().

Signed-off-by: Avi Kivity <avi@qumranet.com>
diff --git a/drivers/kvm/kvm_main.c b/drivers/kvm/kvm_main.c
index 9dd6ad3..7939b5c 100644
--- a/drivers/kvm/kvm_main.c
+++ b/drivers/kvm/kvm_main.c
@@ -769,6 +769,10 @@
 
 	preempt_notifier_init(&vcpu->preempt_notifier, &kvm_preempt_ops);
 
+	r = kvm_arch_vcpu_setup(vcpu);
+	if (r)
+		goto vcpu_destroy;
+
 	mutex_lock(&kvm->lock);
 	if (kvm->vcpus[n]) {
 		r = -EEXIST;