Re: [PATCH v1 09/11] KVM: x86: reset lapic base in kvm_lapic_reset

Paolo Bonzini
2016-07-01T08:46:27Z

On 30/06/2016 22:54, Radim Krčmář wrote:
> LAPIC is reset in xAPIC mode and the surrounding code expects that.
> KVM never resets after initialization. This patch is just for sanity.
>
> Signed-off-by: Radim Krčmář <rkrcmar@redhat.com>
> ---
> arch/x86/kvm/lapic.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 143df33f451e..46eb71c425cf 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -1758,8 +1758,11 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
> /* Stop the timer in case it's a reset to an active apic */
> hrtimer_cancel(&apic->lapic_timer.timer);
>
> - if (!init_event)
> + if (!init_event) {
> + kvm_lapic_set_base(vcpu, APIC_DEFAULT_PHYS_BASE |
> + MSR_IA32_APICBASE_ENABLE);
> kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
> + }
> kvm_apic_set_version(apic->vcpu);
>
> for (i = 0; i < KVM_APIC_LVT_NUM; i++)
> @@ -1898,9 +1901,6 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)
> * thinking that APIC satet has changed.
> */
> vcpu->arch.apic_base = MSR_IA32_APICBASE_ENABLE;
> - kvm_lapic_set_base(vcpu,
> - APIC_DEFAULT_PHYS_BASE | MSR_IA32_APICBASE_ENABLE);
> -
> static_key_slow_inc(&apic_sw_disabled.key); /* sw disabled at reset */
> kvm_lapic_reset(vcpu, false);
> kvm_iodevice_init(&apic->dev, &apic_mmio_ops);
>

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>