Re: [PATCH v2 0/5] Add support for EPT execute only for nested hypervisors

Paolo Bonzini
2016-07-14T06:56:37Z

On 13/07/2016 17:47, Bandan Das wrote:
>>> I wanted to keep it the former way because "PT_PRESENT_MASK is equal to VMX_EPT_READABLE_MASK"
>>> is an assumption all throughout. I wanted to use this section to catch mismatches.
>>
>> I think there's no such assumption anymore, actually. Can you double
>> check? If there are any, that's where the BUILD_BUG_ON should be.
>
> What I meant is how they are the same bit. is_shadow_present_pte() is probably one
> and another one is link_shadow_page() which already has a BUILD_BUG_ON().

You're right about link_shadow_page()! We probably should change the
PT_PRESENT_MASK to shadow_present_mask there (and then readability in
the EPT execonly case is still provided by shadow_user_mask).

For is_shadow_present_pte() you have removed it in patch 1 though.

Paolo