From mboxrd@z Thu Jan  1 00:00:00 1970
From: Anthony Liguori <aliguori@linux.vnet.ibm.com>
Subject: Re: [PATCH  -v2] Monitor command: pfa2hva, translate guest	physical
 address to host virtual address
Date: Sun, 07 Nov 2010 21:39:17 -0600
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Cc: Avi Kivity <avi@redhat.com>, Marcelo Tosatti <mtosatti@redhat.com>,
	Anthony Liguori <aliguori@us.ibm.com>,
	"kvm@vger.kernel.org" <kvm@vger.kernel.org>,
	Andi Kleen <andi@firstfloor.org>,
	Dean Nelson <dnelson@redhat.com>,
	Luiz Capitulino <lcapitulino@redhat.com>
To: Huang Ying <ying.huang@intel.com>
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On 11/07/2010 07:29 PM, Huang Ying wrote:
> On Sun, 2010-11-07 at 00:24 +0800, Avi Kivity wrote:
>    
>> On 11/01/2010 03:22 PM, Anthony Liguori wrote:
>>      
>>> On 11/01/2010 02:20 PM, Huang Ying wrote:
>>>        
>>>> Yes. As general interface, it may not work so well, but as test
>>>> interface, it works quite well and useful.
>>>>
>>>> Do we have any mechanism to add a test only interface?
>>>>          
>>> I'd like to see what Luiz/Markus think but definitely only a human
>>> monitor interface and probably prefix the command with a 'x-' prefix
>>> to indicate that it's not a supported interface.
>>>
>>>        
>> Automated testing will want to use qmp.
>>      
> Yes. The main usage of the interface is automated testing.
>    

That's precisely what the command should not be used for.

You can't assume a gpa -> hva mapping is consistent in an external 
application.  If you want to implement an interface for testing, you 
have to push more of the logic into QEMU to avoid the race.

Regards,

Anthony Liguori

>>> The documentation should be very clear about the limitations of the
>>> interface and the intended use-case.
>>>
>>>        
>> Perhaps a { execute: 'enable-version-specific-commands', arguments:
>> ['pfa2hva'] } ?
>>      
> Best Regards,
> Huang Ying
>
>
>