On 14/07/2016 19:38, Bandan Das wrote: > Paolo Bonzini <pbonzini@xxxxxxxxxx> writes: > >> 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). > > Makes sense. Would you like a new version with that added or can that be a > separate patch ? I've already done it and pushed it to kvm/next. :) >> For is_shadow_present_pte() you have removed it in patch 1 though. > > Right. But the assumption is still that is_shadow_present_pte() works because > EPT_READABLE and PT_PRESENT are the same. is_shadow_present_pte() tests 0xFFFFFFFF, so it does not depend on bit 0 alone, for neither EPT nor "normal" page tables. Paolo -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
