some more testing... instance has a tpm configured in acs, its a kvm guest on ubuntu
root@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# echo "Hello, TPM!" > datafile root@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvwrite -C o -i datafile 0x1500016 root@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvread -C o 0x1500016 WARN: Reading full size of the NV index Hello, TPM! Instance power cycle, and trying to read our value again from the tpm root@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6:~# tpm2_nvread -C o 0x1500016 WARN: Reading full size of the NV index WARNING:esys:src/tss2-esys/api/Esys_NV_ReadPublic.c:309:Esys_NV_ReadPublic_Finish() Received TPM Error ERROR:esys:src/tss2-esys/esys_tr.c:243:Esys_TR_FromTPMPublic_Finish() Error NV_ReadPublic ErrorCode (0x0000018b) ERROR:esys:src/tss2-esys/esys_tr.c:398:Esys_TR_FromTPMPublic() Error TR FromTPMPublic ErrorCode (0x0000018b) ERROR: Esys_TR_FromTPMPublic(0x18B) - tpm:handle(1):the handle is not correct for the use ERROR: Unable to run tpm2_nvread root@VM-647bf7bc-bdca-48fa-8329-8b7a103f9ab6: its gone. Is this tpm just here to satisfy requirements? Or do i miss something? If its not persistant, the docs should clearly tell the limitations Cheers, Juergen Am 14.10.25, 13:24 schrieb "Jürgen Gotteswinter" <[email protected] <mailto:[email protected]>LID>: Hello Mailinglist, i am currently looking at the software tpm integration, and i wonder a bit on how this works and especially where the tpm data is persisted. I can see that a vm which has a tpm configured creates a folder in /var/lib/libvirt/swtpm/<UUID>/tpm2/ with 2 files tpm2-00-permall and a .lock file. When i migrate the vm to another compute host, this folder gets created on the target. I did not yet test to store any data in the tpm, does anyone know how and where (or even if) this gets persisted? ACS 4.20.1.0 Ubuntu 24.04 + KVM Thanks! Juergen
