[RFC PATCH 05/67] KVM: Enable hardware before doing arch VM initialization

[isaku . yamahata]

From: Sean Christopherson <sean.j.christopher...@intel.com>

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.christopher...@intel.com>
---
 virt/kvm/kvm_main.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c
index 65e1737c4354..11166e901582 100644
--- a/virt/kvm/kvm_main.c
+++ b/virt/kvm/kvm_main.c
@@ -764,7 +764,7 @@ static struct kvm *kvm_create_vm(unsigned long type)
                struct kvm_memslots *slots = kvm_alloc_memslots();
 
                if (!slots)
-                       goto out_err_no_arch_destroy_vm;
+                       goto out_err_no_disable;
                /* Generations must be different for each address space. */
                slots->generation = i;
                rcu_assign_pointer(kvm->memslots[i], slots);
@@ -774,19 +774,19 @@ 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
@@ -813,10 +813,10 @@ 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));
-- 
2.17.1