Re: [PATCH 2/2] tpm: add backend for mssim

[Stefan Berger]

On 1/9/23 12:55, James Bottomley wrote:
> On Mon, 2023-01-09 at 17:52 +0000, Dr. David Alan Gilbert wrote:
> > * James Bottomley (jejb@linux.ibm.com) wrote:
> [...]
> > > external MSSIM TPM emulator has to be kept running to preserve the
> > > state.  If you restart it, the migration will fail.
> >
> > Document that and we're getting there.
>
>
> The documentation in the current patch series says
>
> ----
> The mssim backend supports snapshotting and migration, but the state
> of the Microsoft Simulator server must be preserved (or the server
> kept running) outside of QEMU for restore to be successful.
> ----
>
> What, beyond this would you want to see?

mssim today lacks the functionality of marshalling and unmarshalling the 
permanent and volatile state of the TPM 2, which are both needed for snapshot 
support. How does this work with mssim?

   Stefan

> James