[systemd-devel] Issues supporting systems with and without TPM and firmware TPM (was Re: Handle device node timeout?)

[Mikko Rapeli]

Hi,

On Fri, Apr 12, 2024 at 05:03:18PM +0300, Aleksandar Kostadinov wrote:
> Shouldn't the kernel automatically load the necessary modues when
> devices are detected... given proper udev rules and module
> availability in the initrd filesystem? I guess it depends on how you
> build your initrd system for including them.

The modules do get loaded but too late in the initramfs stage and something
in the tpm2.target and related service was failing and creating TPM2 encrypted
rootfs fails. I could not figure out at which stage the driver needs to be loaded,
e.g.
Before: modprobe at tpm_tis_core.service modprobe at tpm_tis.service modprobe at tpm_ftpm_tee.service

But I'm also trying to fix the root causes why TPM modules can't be built into the
kernel so lucky that resolves these issues. Would be nice to know to which stage
the TPM2 module loading would need to happen though.

Cheers,

-Mikko