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Date: Mon, 23 Aug 2010 08:48:18 +0300
From: Avi Kivity <avi@redhat.com>
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Subject: Re: [Qemu-devel] [PATCH v2 0/7] APIC/IOAPIC cleanup
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To: Anthony Liguori <anthony@codemonkey.ws>
Cc: Blue Swirl <blauwirbel@gmail.com>, "Liu >> \"Liu,
	Jinsong\"" <jinsong.liu@intel.com>, qemu-devel <qemu-devel@nongnu.org>, Paul Brook <paul@codesourcery.com>

  On 08/23/2010 12:07 AM, Anthony Liguori wrote:
> On 08/22/2010 02:44 PM, Avi Kivity wrote:
>>> No more MI diamond and all devices have DeviceStates.  
>>> Coincidentally, it matches more closely how hardware works..
>>>
>>
>>
>> Well, I agree, but I honestly lost the context.  How does this relate 
>> to the APIC and cpu hotplug?
>>
>> I'll take the opportunity to say that we should be using a language 
>> that has first-class (...) support for these concepts instead of 
>> having to divine them from the code.
>
> At the risk of sounding uncool, I think what we really need is a UML 
> diagram describing the device tree.  It's really not that much more 
> difficult to create a similar mess in C++.
>

That's fine near a whiteboard with some airspace for handwaving.  
Doesn't work well through patches and email.

The advantage of better language support is that it's easier to 
resurrect the model from the code; it doesn't give you a better or worse 
model by itself.

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