> What do you call "hinting ends" though? The fact we put
> a page in the VQ is not a guarantee that it's been consumed
> by the hypervisor.
>
I'd say hinting ends once the hypervisor sets FREE_PAGE_REPORT_S_DONE.
>
> I think a strict definition is this:
> - hint includes a command ID
> - hint implies "page was unused at some point after guest reading command ID"
>
>
> Hypervisor can use dirty tracking tricks to get from that to
> "page is unused at the moment".
>
>> Whereby X is
>> currently assumed to be 0, correct?
>
>
>
> Now we are talking about what's safe to do with the page.
>
> If POISON flag is set by hypervisor but clear by guest,
> or poison_val is 0, then it's clear it's safe to blow
> away the page if we can figure out it's unused.
>
> Otherwise, it's much less clear :)
Hah! Agreed :D
>
>
>
> I'll have to come back and re-read the rest next week, this
> is complex stuff and I'm too rushed with other things today.
Yeah, I'm also loaded with other stuff. Maybe Alex has time to
understand the details as well.
--
Thanks,
David / dhildenb
