Re: [PATCH v2 0/2] fix failure of integration IMA with tpm_crb_ffa

From: Yeoreum Yun
Date: Thu Jun 12 2025 - 09:29:09 EST


Hi Jarkko,

[...]
> Yep, and you sort it out by not compiling it as a module.
>
> + ret = ffa_register(&tpm_crb_ffa_driver);
> + BUG_ON(!ret && !tpm_crb_ffa);
>
> These lines struck me in your patch. The commit message has nothing
> about ffa_register().


Sorry. I think I miss the description for this detail.

This is core of this patch.
So, in patch #1, by chaning the ffa_init() to rootfs_initcall,
it ensures the generation of "tpm_crb_ffa device" is created before
crb_acpi_driver_init() but "tpm_crb_ffa device" isn't probe yet since
the "tpm_crb_ffa driver" isn't yet registered which is registered by
"tpm_crb_ffa_init()".

Therefore, this patch does that when crb_acpi_driver_init() is called first,
tpm_crb_init() registers "tpm_crb_ffa driver" via "ffa_register()"
to trigger probing of "tpm_crb_ffa device" to initalize
the TPM device using CRB over FF-A.

>
> Also, please remove BUG_ON(). That said, I don't think 2/2 is needed.

Okay. I'll replace it with error message.

Thanks.

--
Sincerely,
Yeoreum Yun