KVM: init bsp_vcpu before kvm_arch_vcpu_init

[Marcelo Tosatti <mtosatti@redhat.com>]

On x86 mp_state is initialized by kvm_arch_vcpu_init. Right
now kvm_vcpu_is_bsp returns false because kvm->bsp_vcpu has
not been initialized, so vcpu_id == 0 ends up with mp_state ==
KVM_MP_STATE_UNINITIALIZED.

Gleb do you see a better way to fix this?


Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>


diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 8939ffa..7225064 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -773,6 +773,13 @@ int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 	struct page *page;
 	int r;
 
+	mutex_lock(&kvm->lock);
+#ifdef CONFIG_KVM_APIC_ARCHITECTURE
+	if (kvm->bsp_vcpu_id == id)
+		kvm->bsp_vcpu = vcpu;
+#endif
+	mutex_unlock(&kvm->lock);
+
 	mutex_init(&vcpu->mutex);
 	vcpu->cpu = -1;
 	vcpu->kvm = kvm;
@@ -1760,14 +1767,12 @@ static int kvm_vm_ioctl_create_vcpu(struct kvm *kvm, u32 id)
 	smp_wmb();
 	atomic_inc(&kvm->online_vcpus);
 
-#ifdef CONFIG_KVM_APIC_ARCHITECTURE
-	if (kvm->bsp_vcpu_id == id)
-		kvm->bsp_vcpu = vcpu;
-#endif
 	mutex_unlock(&kvm->lock);
 	return r;
 
 vcpu_destroy:
+	if (kvm->bsp_vcpu_id == id)
+		kvm->bsp_vcpu = NULL;
 	mutex_unlock(&kvm->lock);
 	kvm_arch_vcpu_destroy(vcpu);
 	return r;