On Thu, Sep 28, 2023, Maxim Levitsky wrote:
> svm_leave_nested() similar to a nested VM exit, get the vCPU out of nested
> mode and thus should end the local inhibition of AVIC on this vCPU.
>
> Failure to do so, can lead to hangs on guest reboot.
>
> Raise the KVM_REQ_APICV_UPDATE request to refresh the AVIC state of the
> current vCPU in this case.
>
> Cc: stable@xxxxxxxxxxxxxxx
Unnecessary newline.
Fixes: f44509f849fe ("KVM: x86: SVM: allow AVIC to co-exist with a nested guest running")
> Signed-off-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
> ---
> arch/x86/kvm/svm/nested.c | 3 +++
> 1 file changed, 3 insertions(+)
>
> diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
> index dd496c9e5f91f28..3fea8c47679e689 100644
> --- a/arch/x86/kvm/svm/nested.c
> +++ b/arch/x86/kvm/svm/nested.c
> @@ -1253,6 +1253,9 @@ void svm_leave_nested(struct kvm_vcpu *vcpu)
>
> nested_svm_uninit_mmu_context(vcpu);
> vmcb_mark_all_dirty(svm->vmcb);
> +
> + if (kvm_apicv_activated(vcpu->kvm))
> + kvm_make_request(KVM_REQ_APICV_UPDATE, vcpu);
> }
>
> kvm_clear_request(KVM_REQ_GET_NESTED_STATE_PAGES, vcpu);
> --
> 2.26.3
>
