Re: [PATCH 1/2] KVM: PIC: call ack notifiers for irqs that are dropped form irr

[Gleb Natapov <gleb@redhat.com>]

On Thu, Jul 26, 2012 at 12:09:36PM +0300, Avi Kivity wrote:
> On 07/26/2012 10:00 AM, Gleb Natapov wrote:
> > After commit 242ec97c358256 PIT interrupts are no longer delivered after
> > PIC reset. It happens because PIT injects interrupt only if previous one
> > was acked, but since on PIC reset it is dropped from irr it will never
> > be delivered and hence acknowledged. Fix that by calling ack notifier on
> > PIC reset.
> > 
> > Signed-off-by: Gleb Natapov <gleb@redhat.com>
> > ---
> >  arch/x86/kvm/i8259.c |   17 +++++++++++++++++
> >  1 file changed, 17 insertions(+)
> > 
> > diff --git a/arch/x86/kvm/i8259.c b/arch/x86/kvm/i8259.c
> > index 81cf4fa..0147d16 100644
> > --- a/arch/x86/kvm/i8259.c
> > +++ b/arch/x86/kvm/i8259.c
> > @@ -305,6 +305,11 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
> >  	addr &= 1;
> >  	if (addr == 0) {
> >  		if (val & 0x10) {
> > +			u8 edge_irr = s->irr & ~s->elcr;
> > +			int i;
> > +			bool found;
> > +			struct kvm_vcpu *vcpu;
> > +
> >  			s->init4 = val & 1;
> >  			s->last_irr = 0;
> >  			s->irr &= s->elcr;
> > @@ -322,6 +327,18 @@ static void pic_ioport_write(void *opaque, u32 addr, u32 val)
> >  			if (val & 0x08)
> >  				pr_pic_unimpl(
> >  					"level sensitive irq not supported");
> > +
> > +			kvm_for_each_vcpu(i, vcpu, s->pics_state->kvm)
> > +				if (kvm_apic_accept_pic_intr(vcpu)) {
> > +					found = true;
> > +					break;
> > +				}
> > +
> > +
> > +			if (found)
> > +				for (irq = 0; irq < PIC_NUM_PINS/2; irq++)
> > +					if (edge_irr & (1 << irq))
> > +						pic_clear_isr(s, irq);
> >  		} else if (val & 0x08) {
> 
> 
> This duplicates the code in pic_reset().  Please extract it into a
> function (just the new code, since this is going into 3.6).
> 
> 
Extract what into a function? I specifically sent follow up patch to
cleanup duplicates.

--
			Gleb.