On Thu, Jan 06, 2022 at 08:53:00AM -0500, Stefan Berger wrote:
On 1/6/22 03:36, Igor Mammedov wrote:
On Tue, 4 Jan 2022 12:58:05 -0500
Stefan Berger <stefanb@linux.ibm.com> wrote:
Add missing TPM device identification objects _STR and _UID. They will
appear as files 'description' and 'uid' under Linux sysfs.
Following inspection of sysfs entries for hardware TPMs we chose
uid '1'.
My guess would be that buy default (in case of missing UID), OSPM
will start enumerate from 0. So I think 0 is more safer choice
when it comes to compatibility.
Can you smoke test TPM with Windows, and check if adding UID doesn't
break anything if VM actually uses TMP (though I'm not sure how to
check it on Windows, maybe install Windows 11 without this patch
and then see if it still boots pre-installed VM and nothing is broken
after this patch)?
I smoke tested it with the posted patches applied to v6.2.0 and started 3
VMs with it:
- Linux shows uid = 1 and the description "TPM 2.0 Device" in sysfs
- Win 10 and Win 11 tpm.msc tool are both showing that the TPM is 'ready for
use'
Stefan
Just to make sure, what Igor was concerned about is issues like
we had with e.g. network devices, when changing UID makes
windows think it's a new device and lose configuration
created on old qemu on boot with a new qemu.
Not sure what can be configured with a TPM device though ...