Re: [PATCHv4 1/8] mm: Add support for unaccepted memory

Dave Hansen
2022-04-11T16:27:24Z

On 4/11/22 08:55, Borislav Petkov wrote:
> On Sun, Apr 10, 2022 at 11:41:57PM -0700, Dave Hansen wrote:
>> Let's just call out the possible (probable?) need for new ABI here.
>> Maybe it will cue folks who care to speak up.
> Err, why would you teach the user to go poke at some arbitrary sysfs
> nodes when the accepting code can simply issue a printk from time to
> time
>
> "Guest unnaccepted memory progress: XX%. This slows down operations at the moment."

I guess that's not a horrible place to start. It's also not *horribly*
different from how guests work today. If hosts lazily allocate RAM,
they'll see largely the same kind of behavior.

What ends up determining how much memory is pre-accepted versus being
done from the guest? Is that just a normal part of setting up a TDX
guest, like from the qemu cmdline? Or, is there some convention with
the virtual firmware?