Re: [Qemu-devel] [Xen-devel] Re: [PATCH] xen: fix interrupt routing

[Avi Kivity]

On 06/15/2011 11:24 AM, Alexander Graf wrote:
> I'm actually not quite sure what exactly he's describing here. But if it's 
> bypassing the bus logic, it's not a normal PCI device :). Sure, there are 
> special case devices that also expose a PCI interface. But real PCI cards that 
> you plug in onto the PCI bus can't bypass the interrupt logic of the bus, as 
> the only interrupt wires they have go to the bus. And since the PCI adapters we 
> use in PC machines in Qemu are all non-special, guests can possibly choke on 
> this.

There actually is a special device in qemu - acpi power management is 
configured as a PCI device, but its interrupt is hard-wired to gsi 9 and 
is edge-triggered (so it can't share the irq line).

I other devices that are special in this regard to also be part of the 
chipset, not devices you can plug into arbitrary slots.

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error compiling committee.c: too many arguments to function