Emulated TPM devices and snapshots of running VMs

[Peter Krempa]

On Thu, Jul 09, 2020 at 14:14:32 +0200, Milan Zamazal wrote:
> Milan Zamazal <mzamazal at redhat.com> writes:
> 
> > Hi,
> >
> > I would like to clarify how to make snapshots of running VMs with
> > emulated TPM devices.  As far as I understand QEMU documentation, it's
> > possible to make snapshots of running VMs with TPM, but it's important
> > to retain the state of swtpm.  Does libvirt assist with that in any way
> > or is it completely user's responsibility?  libvirt pauses the VM
> > internally when making a snapshot, which should be the right moment to
> > copy the swtpm data, but the user doesn't have control over it.  Is
> > there a way to make a copy of swtpm data that is guaranteed to be
> > consistent with the snapshot?
> 
> No idea?

I can comment only on the fact that libvirt doesn't do anything
regarding snapshots on a VM with TPM.