Re: List of unaccessible x86 states

[Avi Kivity <avi@redhat.com>]

On 10/26/2009 11:17 AM, Joerg Roedel wrote:
> On Sun, Oct 25, 2009 at 11:49:35AM +0200, Avi Kivity wrote:
>    
>> On 10/24/2009 12:35 PM, Alexander Graf wrote:
>>      
>>> Hm, thinking about this again, it might be useful to have an
>>> "currently in nested VM" flag here. That way userspace can decide
>>> if it needs to get out of the nested state (for migration) or if
>>> it just doesn't care.
>>>        
>> Getting out of nested state involves modifying state (both memory
>> and registers).  Nor can we in the general case force it.  The guest
>> can set up a situation where it is impossible to #vmexit.
>>      
> There is actually more than that. If the guest runs in guest mode itself
> we also need to report the host state to be able to do an #vmexit after
> migration.
> In nested SVM the host state is not saved in the guest memory to prevent
> the guest from modifying it and break out of its virtualization jail.
>    

Which host state?  As far as I can tell, it can all be regenerated.

-- 
error compiling committee.c: too many arguments to function