On Sun, 2022-02-20 at 20:19 -0600, Suravee Suthikulpanit wrote:
> The kvm_x86_ops.vcpu_(un)blocking are needed by AVIC only.
> Therefore, set the ops only when AVIC is enabled.
>
> Suggested-by: Sean Christopherson <seanjc@xxxxxxxxxx>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> ---
> arch/x86/kvm/svm/avic.c | 12 ++++++++++--
> arch/x86/kvm/svm/svm.c | 7 -------
> arch/x86/kvm/svm/svm.h | 2 --
> 3 files changed, 10 insertions(+), 11 deletions(-)
>
> diff --git a/arch/x86/kvm/svm/avic.c b/arch/x86/kvm/svm/avic.c
> index abde08ca23ab..0040824e4376 100644
> --- a/arch/x86/kvm/svm/avic.c
> +++ b/arch/x86/kvm/svm/avic.c
> @@ -996,7 +996,7 @@ void avic_vcpu_put(struct kvm_vcpu *vcpu)
> WRITE_ONCE(*(svm->avic_physical_id_cache), entry);
> }
>
> -void avic_vcpu_blocking(struct kvm_vcpu *vcpu)
> +static void avic_vcpu_blocking(struct kvm_vcpu *vcpu)
> {
> if (!kvm_vcpu_apicv_active(vcpu))
> return;
> @@ -1021,7 +1021,7 @@ void avic_vcpu_blocking(struct kvm_vcpu *vcpu)
> preempt_enable();
> }
>
> -void avic_vcpu_unblocking(struct kvm_vcpu *vcpu)
> +static void avic_vcpu_unblocking(struct kvm_vcpu *vcpu)
> {
> int cpu;
>
> @@ -1057,6 +1057,14 @@ bool avic_hardware_setup(struct kvm_x86_ops *x86_ops)
> pr_info("x2AVIC enabled\n");
> }
>
> + if (avic_mode) {
> + x86_ops->vcpu_blocking = avic_vcpu_blocking;
> + x86_ops->vcpu_unblocking = avic_vcpu_unblocking;
> + } else {
> + x86_ops->vcpu_blocking = NULL;
> + x86_ops->vcpu_unblocking = NULL;
> + }
> +
> amd_iommu_register_ga_log_notifier(&avic_ga_log_notifier);
> return !!avic_mode;
> }
> diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
> index 3048f4b758d6..3687026f2859 100644
> --- a/arch/x86/kvm/svm/svm.c
> +++ b/arch/x86/kvm/svm/svm.c
> @@ -4531,8 +4531,6 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
> .prepare_guest_switch = svm_prepare_guest_switch,
> .vcpu_load = svm_vcpu_load,
> .vcpu_put = svm_vcpu_put,
> - .vcpu_blocking = avic_vcpu_blocking,
> - .vcpu_unblocking = avic_vcpu_unblocking,
>
> .update_exception_bitmap = svm_update_exception_bitmap,
> .get_msr_feature = svm_get_msr_feature,
> @@ -4819,11 +4817,6 @@ static __init int svm_hardware_setup(void)
>
> enable_apicv = avic = avic && avic_hardware_setup(&svm_x86_ops);
>
> - if (!enable_apicv) {
> - svm_x86_ops.vcpu_blocking = NULL;
> - svm_x86_ops.vcpu_unblocking = NULL;
> - }
Isn't this code already zeros these callbacks when avic is not enabled?
I am not sure why this patch is needed to be honest.
Best regards,
Maxim Levitsky
> -
> if (vls) {
> if (!npt_enabled ||
> !boot_cpu_has(X86_FEATURE_V_VMSAVE_VMLOAD) ||
> diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h
> index b53c83a44ec2..1a0bf6b853df 100644
> --- a/arch/x86/kvm/svm/svm.h
> +++ b/arch/x86/kvm/svm/svm.h
> @@ -578,8 +578,6 @@ void svm_hwapic_isr_update(struct kvm_vcpu *vcpu, int max_isr);
> bool svm_dy_apicv_has_pending_interrupt(struct kvm_vcpu *vcpu);
> int svm_update_pi_irte(struct kvm *kvm, unsigned int host_irq,
> uint32_t guest_irq, bool set);
> -void avic_vcpu_blocking(struct kvm_vcpu *vcpu);
> -void avic_vcpu_unblocking(struct kvm_vcpu *vcpu);
> void avic_ring_doorbell(struct kvm_vcpu *vcpu);
>
> /* sev.c */
