Re: [ANNOUNCE] KVM Microconference at LPC 2023

[Sean Christopherson <seanjc@google.com>]

On Fri, May 26, 2023, Sean Christopherson wrote:
> On Fri, May 26, 2023, James Gowans wrote:
> > On Tue, 2023-05-09 at 11:55 +0200, Paolo Bonzini wrote:
> > > Hi all!
> > > 
> > > We are planning on submitting a CFP to host a KVM Microconference at
> > > Linux Plumbers Conference 2023. To help justify the proposal, we would
> > > like to gather a list of folks that would likely attend, and crowdsource
> > > a list of topics to include in the proposal.
> > 
> > Hi Paolo,
> > 
> > This MC sounds great! There are two topics I'd be keen to discuss, both in
> > the KVM + memory-management realm:
> > 
> > 1. Guest and kernel memory persistence across kexec for live update.
> > Specifically focussing on the host IOMMU pgtable persistence for DMA-
> > passthrough devices to support kexec while guest-driven DMA is still
> > running. There is some discussion happening now about this [1] and
> > hopefully the discussion and prototyping will continue in the run up to
> > LPC.
> 
> I don't think a KVM MC conference would be the right venue for this discussion.
> IIUC, KVM does not need to be involved in preserving guest memory or the IOMMU
> page tables.

Ah, I assume the KVM involvement comes from a potentially new filesystem for guest
memory?

  5. More "advanced" memory management APIs/ioctls for virtualisation: Being
  able to support things like DMA-driven post-copy live migration, memory
  oversubscription, carving out chunks of memory from a VM to launch side-
  car VMs, more fine-grain control of IOMMU or MMU permissions, etc. This
  may be easier to achieve with a new filesystem, rather than coupling to
  tempfs semantics and ioctls.