From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marcelo Tosatti <mtosatti@redhat.com>
Date: Wed, 11 Jun 2008 18:58:37 +0000
Subject: Re: [PATCH] kvm-ia64 irq assignment 2/2 userspace
Message-Id: <20080611185837.GA13245@dmt.cnet>
List-Id: <kvm-ia64.vger.kernel.org>
References: <51CFAB8CB6883745AE7B93B3E084EBE201CC8760@pdsmsx412.ccr.corp.intel.com>
In-Reply-To: <51CFAB8CB6883745AE7B93B3E084EBE201CC8760@pdsmsx412.ccr.corp.intel.com>
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To: kvm-ia64@vger.kernel.org

> > @@ -220,6 +232,11 @@ static void piix3_set_irq(qemu_irq *pic, int
> > irq_num, int level)
> >  {
> >      int i, pic_irq, pic_level;
> > 
> > +#if defined(KVM_CAP_IRQCHIP) && defined(TARGET_IA64)
> > +    if(kvm_enabled())
> > +        kvm_set_irq(irq_num, level);
> > +    return;
> > +#endif
> >      pci_irq_levels[irq_num] = level;
> 
> Why the current hook into i8259_set_irq does not work for IA64? 

    if (pic_irq < 16) {
        /* The pic level is the logical OR of all the PCI irqs mapped
           to it */

Ok, but still, how can you share interrupts by directly changing the
level without checking for individual devices first.

> I think this breaks interrupt sharing, because the logic to detect if
> all devices sharing the line are low or high is in i8259_set_irq, and

s/i8259_set_irq/piix3_set_irq/

> you simply skip that.