Re: [PATCH] KVM: LAPIC: Fix a spelling mistake in comments

[Sean Christopherson]

On Tue, Jul 12, 2022, Sean Christopherson wrote:
> On Fri, Jul 01, 2022, Zhang Jiaming wrote:
> ---
>  arch/x86/kvm/lapic.c | 15 +++++++++------
>  1 file changed, 9 insertions(+), 6 deletions(-)
> 
> diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
> index 48740a235dee..ef5417d3ce95 100644
> --- a/arch/x86/kvm/lapic.c
> +++ b/arch/x86/kvm/lapic.c
> @@ -830,13 +830,16 @@ static bool kvm_apic_match_physical_addr(struct kvm_lapic *apic, u32 mda)
>  		return mda == kvm_x2apic_id(apic);
> 
>  	/*
> -	 * Hotplug hack: Make LAPIC in xAPIC mode also accept interrupts as if
> -	 * it were in x2APIC mode.  Hotplugged VCPUs start in xAPIC mode and
> -	 * this allows unique addressing of VCPUs with APIC ID over 0xff.
> -	 * The 0xff condition is needed because writable xAPIC ID.

Doh, this won't apply on kvm/queue, I unintentionally generated this as a delta
on top of your patch.  I'll remedy that before testing and officially posting.

> +	 * Hotplug hack: Accept interrupts for vCPUs in xAPIC mode as if they
> +	 * were in x2APIC mode if the target APIC ID can't be encoded as an
> +	 * xAPIC ID.  This allows unique addressing of hotplugged vCPUs (which
> +	 * start in xAPIC mode) with an APIC ID that is unaddressable in xAPIC
> +	 * mode.  Match the x2APIC ID if and only if the target APIC ID can't
> +	 * be encoded in xAPIC to avoid spurious matches against a vCPU that
> +	 * changed its (addressable) xAPIC ID (which is writable).
>  	 */
> -	if (kvm_x2apic_id(apic) > 0xff && mda == kvm_x2apic_id(apic))
> -		return true;
> +	if (mda > 0xff)
> +		return mda == kvm_x2apic_id(apic);
> 
>  	return mda == kvm_xapic_id(apic);
>  }
> 
> base-commit: ba0d159dd8844469d4e4defff4985a7b80f956e9
> --
>