[PATCH v2] kvm: x86: Do proper cleanup if kvm_x86_ops->vm_init() fails

[PATCH v2] kvm: x86: Do proper cleanup if kvm_x86_ops->vm_init() fails

[Junaid Shahid]

If vm_init() fails [which can happen, for instance, if a memory
allocation fails during avic_vm_init()], we need to cleanup some
state in order to avoid resource leaks.

Signed-off-by: Junaid Shahid <junaids@google.com>
---
v2:
- Moved the vm_init() call earlier in kvm_arch_init_vm()

 arch/x86/kvm/x86.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f389691d8c04..547e55d6b662 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -12029,6 +12029,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	if (ret)
 		goto out_page_track;
 
+	ret = static_call(kvm_x86_vm_init)(kvm);
+	if (ret)
+		goto out_uninit_mmu;
+
 	INIT_HLIST_HEAD(&kvm->arch.mask_notifier_list);
 	INIT_LIST_HEAD(&kvm->arch.assigned_dev_head);
 	atomic_set(&kvm->arch.noncoherent_dma_count, 0);
@@ -12064,8 +12068,10 @@ int kvm_arch_init_vm(struct kvm *kvm, unsigned long type)
 	kvm_hv_init_vm(kvm);
 	kvm_xen_init_vm(kvm);
 
-	return static_call(kvm_x86_vm_init)(kvm);
+	return 0;
 
+out_uninit_mmu:
+	kvm_mmu_uninit_vm(kvm);
 out_page_track:
 	kvm_page_track_cleanup(kvm);
 out:

base-commit: a4850b5590d01bf3fb19fda3fc5d433f7382a974
-- 
2.37.1.455.g008518b4e5-goog

Re: [PATCH v2] kvm: x86: Do proper cleanup if kvm_x86_ops->vm_init() fails

[Sean Christopherson]

On Fri, Jul 29, 2022, Junaid Shahid wrote:
> If vm_init() fails [which can happen, for instance, if a memory
> allocation fails during avic_vm_init()], we need to cleanup some
> state in order to avoid resource leaks.
> 
> Signed-off-by: Junaid Shahid <junaids@google.com>
> ---

Pushed to branch `for_paolo/6.1` at:

    https://github.com/sean-jc/linux.git

Unless you hear otherwise, it will make its way to kvm/queue "soon".

Note, the commit IDs are not guaranteed to be stable.