[RFC PATCH v5 004/104] KVM: Enable hardware before doing arch VM initialization

[isaku . yamahata]

From: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>

Swap the order of hardware_enable_all() and kvm_arch_init_vm() to
accommodate Intel's TDX, which needs VMX to be enabled during VM init in
order to make SEAMCALLs.

This also provides consistent ordering between kvm_create_vm() and
kvm_destroy_vm() with respect to calling kvm_arch_destroy_vm() and
hardware_disable_all().

Signed-off-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
Signed-off-by: Isaku Yamahata <isaku.yamahata@xxxxxxxxx>
---
 virt/kvm/kvm_main.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 0afc016cc54d..52f72a366beb 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -1105,19 +1105,19 @@ static struct kvm *kvm_create_vm(unsigned long type)
 		rcu_assign_pointer(kvm->buses[i],
 			kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL_ACCOUNT));
 		if (!kvm->buses[i])
-			goto out_err_no_arch_destroy_vm;
+			goto out_err_no_disable;
 	}
 
 	kvm->max_halt_poll_ns = halt_poll_ns;
 
-	r = kvm_arch_init_vm(kvm, type);
-	if (r)
-		goto out_err_no_arch_destroy_vm;
-
 	r = hardware_enable_all();
 	if (r)
 		goto out_err_no_disable;
 
+	r = kvm_arch_init_vm(kvm, type);
+	if (r)
+		goto out_err_no_arch_destroy_vm;
+
 #ifdef CONFIG_HAVE_KVM_IRQFD
 	INIT_HLIST_HEAD(&kvm->irq_ack_notifier_list);
 #endif
@@ -1145,10 +1145,10 @@ static struct kvm *kvm_create_vm(unsigned long type)
 		mmu_notifier_unregister(&kvm->mmu_notifier, current->mm);
 #endif
 out_err_no_mmu_notifier:
-	hardware_disable_all();
-out_err_no_disable:
 	kvm_arch_destroy_vm(kvm);
 out_err_no_arch_destroy_vm:
+	hardware_disable_all();
+out_err_no_disable:
 	WARN_ON_ONCE(!refcount_dec_and_test(&kvm->users_count));
 	for (i = 0; i < KVM_NR_BUSES; i++)
 		kfree(kvm_get_bus(kvm, i));
-- 
2.25.1