Missing boot related measurements at TPM 2.0 PCRs 0-7 with OVMF

["Ricardo Araújo" <ricardo@lsd.ufcg.edu.br>]

Hi everyone, 

I'm using OVMF with a simulated TPM 2.0 (from https://github.com/stefanberger/swtpm) and I noticed lately that PCRs 0-7 are zeroed after booting the vm (ubuntu 18.04) and the only message related to this in dmesg is: 

[ 2.286690] tpm_tis 00:06: 2.0 TPM (device-id 0x1, rev-id 1) 
[ 2.303753] tpm tpm0: A TPM error (256) occurred continue selftest 
[ 2.314199] tpm tpm0: starting up the TPM manually 

I found this started to happen after this commit , previous commits to that are showing boot time measurements on PCR 0-7 normally and the error message is gone. Has anyone experienced the same behavior? I followed the instructions here for building OVMF but I added the parameters -D TPM2_ENABLE=TRUE -D SECURE_BOOT_ENABLE=TRUE -D HTTP_BOOT_ENABLE=TRUE. Is there anything else I need to add to enable these measurements? 

Regards, 

Ricardo Araujo 
www.lsd.ufcg.edu.br/~ricardo