Re: [Qemu-devel] [PATCH] pc: Clean up PIC-to-APIC IRQ path

[Avi Kivity]

On 08/30/2011 10:19 PM, Blue Swirl wrote:
> >
> >  We need some kind of two phase restore. In the first phase all state is
> >  restored; since some of that state drivers outputs that are input to other
> >  devices, they may experience an edge, and we need to supress that.  In the
> >  second phase edge detection is unsupressed and the device goes live.
>
> No. Devices may not perform any externally visible activities (like
> toggle a qemu_irq) during or after load because 1) qemu_irq is
> stateless and 2) since the receiving end is also freshly loaded, both
> states are already in synch without any calls or toggling.

That makes it impossible to migrate level-triggered irq lines.  Or at 
least, the receiver has to remember the state, instead of (or in 
addition to) the sender.

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error compiling committee.c: too many arguments to function