On Mon, 2022-05-09 at 13:18 +0300, Maxim Levitsky wrote:
> On Sat, 2022-05-07 at 21:39 -0500, Suravee Suthikulpanit wrote:
> > APICv should be deactivated on vCPU that has APIC disabled.
> > Therefore, call kvm_vcpu_update_apicv() when changing
> > APIC mode, and add additional check for APIC disable mode
> > when determine APICV activation,
> >
> > Suggested-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
> > Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> > ---
> > arch/x86/kvm/lapic.c | 4 +++-
> > arch/x86/kvm/x86.c | 4 +++-
> > 2 files changed, 6 insertions(+), 2 deletions(-)
> >
> > diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> > index 8b8c4a905976..680824d7aa0d 100644
> > --- a/arch/x86/kvm/lapic.c
> > +++ b/arch/x86/kvm/lapic.c
> > @@ -2346,8 +2346,10 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value)
> > if (((old_value ^ value) & X2APIC_ENABLE) && (value & X2APIC_ENABLE))
> > kvm_apic_set_x2apic_id(apic, vcpu->vcpu_id);
> >
> > - if ((old_value ^ value) & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE))
> > + if ((old_value ^ value) & (MSR_IA32_APICBASE_ENABLE | X2APIC_ENABLE)) {
> > + kvm_vcpu_update_apicv(vcpu);
> > static_call_cond(kvm_x86_set_virtual_apic_mode)(vcpu);
>
> As futher optimization, we might even get rid of .set_virtual_apic_mode
> and do all of this in kvm_vcpu_update_apicv.
> But no need to this now.
>
>
> > + }
> >
> > apic->base_address = apic->vcpu->arch.apic_base &
> > MSR_IA32_APICBASE_BASE;
> > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> > index 8ee8c91fa762..77e49892dea1 100644
> > --- a/arch/x86/kvm/x86.c
> > +++ b/arch/x86/kvm/x86.c
> > @@ -9836,7 +9836,9 @@ void kvm_vcpu_update_apicv(struct kvm_vcpu *vcpu)
> >
> > down_read(&vcpu->kvm->arch.apicv_update_lock);
> >
> > - activate = kvm_vcpu_apicv_activated(vcpu);
> > + /* Do not activate APICV when APIC is disabled */
> > + activate = kvm_vcpu_apicv_activated(vcpu) &&
> > + (kvm_get_apic_mode(vcpu) != LAPIC_MODE_DISABLED);
> >
> > if (vcpu->arch.apicv_active == activate)
> > goto out;
>
> Looks good!
>
> Reviewed-by: Maxim Levitsky <mlevitsk@xxxxxxxxxx>
>
> Best regards,
> Maxim Levitsky
>
Sorry for a duplicated reply - I tried to cancel it
to correct a typo, but I was too late I see.
Best regards,
Maxim Levitsky
