Re: ima - wait for tpm load

From: Mimi Zohar
Date: Thu Jun 10 2021 - 10:20:20 EST


[Cc'ing Jarkko]

On Thu, 2021-06-10 at 09:16 +0200, Jorge Ramirez-Ortiz, Foundries
wrote:
> I am enabling IMA on a ZynqMP based platform using an SPI based TPM
> from Infineon.
>
> The SPI TPM driver is built-in but since the IMA is initalized from a
> late_initcall, IMA never finds the TPM.
>
> Is there a recomended way to work around this issue?
>
> fio@uz3cg-dwg:~$ dmesg | grep tpm
> [ 3.381181] tpm_tis_spi spi1.1: 2.0 TPM (device-id 0x1B, rev-id 22)
> [ 3.423608] tpm tpm0: A TPM error (256) occurred attempting the self test
> [ 3.430406] tpm tpm0: starting up the TPM manually
>
> fio@uz3cg-dwg:~$ dmesg | grep ima
> [ 3.525741] ima: No TPM chip found, activating TPM-bypass!
> [ 3.531233] ima: Allocated hash algorithm: sha1

Lengthening the TPM timeout, executing the TPM self test have been past
reasons for the TPM not to initialize prior to IMA.

(Missing from this bug report is the kernel version.)

thanks,

Mimi