Re: [RFC] KVM: mm: fd-based approach for supporting KVM guest private memory

On Thu, Aug 26, 2021, at 2:26 PM, David Hildenbrand wrote:

On 26.08.21 19:05, Andy Lutomirski wrote:

quoted

Oof.  That's quite a requirement.  What's the point of the VMA once all
this is done?

You can keep using things like mbind(), madvise(), ... and the GUP code 
with a special flag might mostly just do what you want. You won't have 
to reinvent too many wheels on the page fault logic side at least.

You can keep calling the functions.  The implementations working is a different story: you can't just unmap (pte_numa-style or otherwise) a private guest page to quiesce it, move it with memcpy(), and then fault it back in.

In any event, adding fd-based NUMA APIs would be quite nice.  Look at the numactl command.