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

[Avi Kivity]

On 08/30/2011 12:06 AM, Jan Kiszka wrote:
> >
> >  Does this need to be save/restored for migration?
>
> Nope, but we need some other measure. I thought to remember the pic was
> refreshing this after load, but I do not find any traces of this now. We
> likely need a post_load handler in the i8259 that re-asserts the IRQ as
> required.

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.

--
I have a truly marvellous patch that fixes the bug which this
signature is too narrow to contain.