On Wed, Aug 04, 2021 at 06:21:31PM +0200, Borys Movchan wrote:
> If something went wrong during the TPM firmware upgrade, like power
> failure or the firmware image file get corrupted, the TPM might end
> up in Upgrade or Failure mode upon the next start. The state is
> persistent between the TPM power cycle/restart.
>
> According to TPM specification:
> * If the TPM is in Upgrade mode, it will answer with TPM2_RC_UPGRADE
> to all commands except Field Upgrade related ones.
> * If the TPM is in Failure mode, it will allow performing TPM
> initialization but will not provide any crypto operations.
> Will happily respond to Field Upgrade calls.
>
> The fix changes the behavior of the `tpm2_auto_startup` function, so
In commit messages, you ought to use imperative form:
"Change the behaviour of tpm2_auto_startup(), ..."
> it tries to detect what mode TPM is running in. If the chip is in the
> Upgrade or Failure mode, the function returns -EIO error code which
> can be used later to adjust driver behavior later.
*How* tpm2_auto_startup() detects the mode?
> After `tpm_chip_register` calls `tpm2_auto_startup` it checks for the
Please remove all these hyphens. They make the commit message a pain
to read. E.g. instead write tpm_chip_register(). This is not Github.
> error code. If the TPM is in Upgrade or Failure mode, set the
> `limited_mode` flag. The calls to `tpm2_get_cc_attrs_tbl`,
> `tpm_add_hwrng` and `tpm_get_pcr_allocation` will fail if the TPM is
> in Failure or Upgrade mode, so use `limited_mode` flag to exclude
> them from the module initialization sequence.
>
> Signed-off-by: Borys Movchan <borysmn@xxxxxxxx>
> ---
>
> Notes:
> Commit message updated
v2:
* Commit message updated.
Notes would be something that had existed already in the first version.
Here we want a simple change log.
/Jarkko
