Re: [PATCH v2 2/2] KVM: LAPIC: Don't need to clear IPI delivery status in x2apic mode

[Wanpeng Li]

On Wed, 1 Apr 2020 at 08:35, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
>
> On 01/04/20 02:19, Wanpeng Li wrote:
> > -             /* No delay here, so we always clear the pending bit */
> > -             val &= ~(1 << 12);
> > +             /* Immediately clear Delivery Status in xAPIC mode */
> > +             if (!apic_x2apic_mode(apic))
> > +                     val &= ~(1 << 12);
>
> This adds a conditional, and the old behavior was valid according to the
> SDM: "software should not assume the value returned by reading the ICR
> is the last written value".

We can queue patch 1/2 separately to catch the merge window. :)

    Wanpeng