Re: [PATCH v5 2/2] tpm: add backend for mssim

[Stefan Berger <stefanb@linux.ibm.com>]

On 1/5/23 08:00, James Bottomley wrote:
> From: James Bottomley <James.Bottomley@HansenPartnership.com>
> 
> The Microsoft Simulator (mssim) is the reference emulation platform
> for the TCG TPM 2.0 specification.
> 
> https://github.com/Microsoft/ms-tpm-20-ref.git
> 
>
> diff --git a/docs/specs/tpm.rst b/docs/specs/tpm.rst
> index 535912a92b..1398735956 100644
> --- a/docs/specs/tpm.rst
> +++ b/docs/specs/tpm.rst
> @@ -270,6 +270,38 @@ available as a module (assuming a TPM 2 is passed through):
>     /sys/devices/LNXSYSTEM:00/LNXSYBUS:00/MSFT0101:00/tpm/tpm0/pcr-sha256/9
>     ...
>   
> +The QEMU TPM Microsoft Simulator Device
> +---------------------------------------
> +
> +The TCG provides a reference implementation for TPM 2.0 written by
> +Microsoft (See `ms-tpm-20-ref`_ on github).  The reference implementation
> +starts a network server and listens for TPM commands on port 2321 and
> +TPM Platform control commands on port 2322, although these can be
> +altered.  The QEMU mssim TPM backend talks to this implementation.  By
> +default it connects to the default ports on localhost:
> +
> +.. code-block:: console
> +
> +  qemu-system-x86_64 <qemu-options> \
> +    -tpmdev mssim,id=tpm0 \
> +    -device tpm-crb,tpmdev=tpm0
> +
> +
> +Although it can also communicate with a remote host, which must be
> +specified as a SocketAddress via json on the command line for each of
> +the command and control ports:
> +
> +.. code-block:: console
> +
> +  qemu-system-x86_64 <qemu-options> \
> +    -tpmdev "{'type':'mssim','id':'tpm0','command':{'type':'inet','host':'remote','port':'2321'},'control':{'type':'inet','host':'remote','port':'2322'}}" \
> +    -device tpm-crb,tpmdev=tpm0
> +
> +
> +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.

My comments to v3 still apply here.

I also just tried migration and on the -incoming side it did not work anymore. Did you test this?

    Stefan