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Date: Mon, 05 Jul 2010 20:45:52 +0300
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Subject: Re: [Qemu-devel] Re: [Bug 599958] Re: Timedrift problems with Win7:
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To: Blue Swirl <blauwirbel@gmail.com>
Cc: Jan Kiszka <jan.kiszka@siemens.com>, Paul Brook <paul@codesourcery.com>, Gleb Natapov <gleb@redhat.com>, "qemu-devel@nongnu.org" <qemu-devel@nongnu.org>

On 07/05/2010 08:12 PM, Blue Swirl wrote:
>
> Since you seem to have gone back to drawing board, how about the
> following design:
>
> Explicit qemu_irqs and muxes for the backwards channel
>
>    
[...]

The question of how to design the thing is secondary to me, at present.  
IMO the first question we have to answer is whether we track interrupts 
by delivery (queued into the core/apic, coalesced by core/apic, or 
masked at the irq controller) or mask/ack (masked before the core, or 
acknowledged by guest software; coalescing can be derived from nr_irq > 
nr_acks).  The two approaches provide different information, I don't 
currently have a feel for which is better.


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