Re: [PATCH v4 19/32] KVM: x86: Explicitly track all possibilities for APIC map's logical modes

[Paolo Bonzini]

On 12/17/22 00:34, Sean Christopherson wrote:
> On Fri, Dec 16, 2022, Sean Christopherson wrote:
> > On Thu, Dec 08, 2022, Maxim Levitsky wrote:
>
> ...
>
> > > > @@ -282,7 +291,8 @@ void kvm_recalculate_apic_map(struct kvm *kvm)
> > > >   		if (!apic_x2apic_mode(apic) && !new->phys_map[xapic_id])
> > > >   			new->phys_map[xapic_id] = apic;
> > > >   
> > > > -		if (!kvm_apic_sw_enabled(apic))
> > > > +		if (new->logical_mode == KVM_APIC_MODE_MAP_DISABLED ||
> > > > +		    !kvm_apic_sw_enabled(apic))
> > > >   			continue;
> > > Very minor nitpick: it feels to me that code that updates the logical mode of the
> > > map, might be better to be in a function, or in 'if', like
> >
> > An if-statement would be rough due to the indentation.  A function works well
> > though, especially if both the physical and logical chunks are put into helpers.
> > E.g. the patch at the bottom (with other fixup for this patch) yields:
> >
> > 	new->max_apic_id = max_id;
> > 	new->logical_mode = KVM_APIC_MODE_SW_DISABLED;
> >
> > 	kvm_for_each_vcpu(i, vcpu, kvm) {
> > 		if (!kvm_apic_present(vcpu))
> > 			continue;
> >
> > 		if (kvm_recalculate_phys_map(new, vcpu, &xapic_id_mismatch)) {
> > 			kvfree(new);
> > 			new = NULL;
> > 			goto out;
> > 		}
> >
> > 		kvm_recalculate_logical_map(new, vcpu);
> > 	}
> >
> > I'll tack that patch on at the end of the series if it looks ok.

Yes, please send as a follow up.

Paolo