On Tue, 2024-04-30 at 17:12 -0400, Stefan Berger wrote:
On 4/30/24 15:08, James Bottomley wrote:
[...]
+The mssim backend supports snapshotting and migration by not
resetting
I don't thing snapshotting is supported because snapshooting would
require you to be able to set the state of the vTPM from the snapshot
you started. I would remove the claim.
I thought we established last time that it can definitely do both (and
I've tested it because you asked me to). Snapshotting and migration
are essentially the same thing, with snapshotting being easier because
it can be done on the same host meaning the same command line
parameters. If you migrate to a different host you need the socket to
point back to the host serving the vTPM.
To do this easily you simply keep the vTPM running while the VM is
undergoing snapshot and migration. If you're thinking of and extended
down time for the snapshot, then it's up to the vTPM implementation to
store the state (or simply keep it running for an extended time doing
nothing).