Re: [kvm-devel] [PATCH 6/6] kvm: qemu: Enable EPT support for real mode

[Avi K. <av...@qu...>]

Yang, Sheng wrote:
> On Thursday 24 April 2008 15:37:53 Avi Kivity wrote:
>   
>> Yang, Sheng wrote:
>>     
>>>> Why not use ept_identity_pagetable != NULL to encode
>>>> ept_identity_pagetable_done?
>>>>         
>>> ept_identity_pagetable_done was used to indicate if the pagetable was
>>> setted up, and ept_identity_pagetable was used to indicate if the page
>>> used for pagetable was allocated... I don't want to run
>>> alloc_identity_pagetable() again and again and again... Another method is
>>> read several bits at the front of page to tell if the pagetable was
>>> setted up, but somehow tricky...
>>>       
>> No, better to avoid tricks.  But rmode_tss is only allocated once, so if
>> you unify the allocations, the identity table will also only be
>> allocated once.
>>     
>
> But set_tss_addr() is a x86_ops, if the identity mapping allocation using the 
> same approach, another null function should be added into SVM side, but this 
> thing is VMX specific one...
>   

We could rename set_tss_addr() to mean 
set_tss_and_ept_identity_pt_addr(), but it looks like the ioctl expects 
just three pages... so let's keep the flag for now.

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