Re: KVM Irq injection

[Gleb Natapov <gleb@redhat.com>]

On Tue, Jul 21, 2009 at 08:57:26AM -0700, Saksena, Abhishek wrote:
> 
> 
> 
> Hi,
> I am building some device models around the KVM and am intersted in injecting IRQs.
> 
> The current LibKVM.h provides following function
> 
> int kvm_inject_irq      (       kvm_context_t<file:///C:/Documents%20and%20Settings/asaksena/Desktop/march_onwards/kvmsocket/doc/htmlkvm/structkvm__context.html>       kvm,
>                 int     vcpu,
>                 unsigned        irq
>         )
> 
> Simulate an external vectored interrupt.
> 
> This allows you to simulate an external vectored interrupt.
> 
> Parameters:
>         kvm     Pointer to the current kvm_context<file:///C:/Documents%20and%20Settings/asaksena/Desktop/march_onwards/kvmsocket/doc/htmlkvm/structkvm__context.html>
>         vcpu    Which virtual CPU should get dumped
>         irq     Vector number
> 
> Returns:
> 0 on success
> 
> My question is if I am say Injecting IRQ on pin 0 on PIC how do I get croosponding vector? I am using KVM's interrupt controllers.
> 
This ioctl should be used if userspace emulates HW that maps IRQ to
interrupt vector (PIC/IOAPIC/LAPIC).

> 
> 
> I also see another function
> 
> 
> 
> int kvm_set_irq_level ( kvm_context_t<file:///C:/Documents%20and%20Settings/asaksena/Desktop/march_onwards/kvmsocket/doc/htmlkvm/structkvm__context.html>  kvm, int  irq, int  level  )
> 
> 
> 
> Can this be used safely to inject IRQ- I am gusseing irq refers to the pin and Level the value of that pin. How do I tell with this function which CPU I want to inject interrupt?
> 
> 
And this one should be used if PIC/IOAPIC/LAPIC are emulated by
a kernel.

--
			Gleb.