Re: [PATCH] tpm: Don't make log failures fatal

From: Paul Menzel <pmenzel@molgen.mpg.de>
To: Matthew Garrett <matthewgarrett@google.com>
Cc: linux-integrity@vger.kernel.org,
	Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
	Matthew Garrett <mjg59@google.com>,
	stable@vger.kernel.org
Subject: Re: [PATCH] tpm: Don't make log failures fatal
Date: Tue, 17 Dec 2019 13:15:14 +0100	[thread overview]
Message-ID: <3a472005-83a7-9787-0bfc-35673702be09@molgen.mpg.de> (raw)
In-Reply-To: <20191213225748.11256-1-matthewgarrett@google.com>

Dear Matthew,

Am 13.12.19 um 23:57 schrieb Matthew Garrett:
> If a TPM is in disabled state, it's reasonable for it to have an empty
> log. Bailing out of probe in this case means that the PPI interface
> isn't available, so there's no way to then enable the TPM from the OS.
> In general it seems reasonable to ignore log errors - they shouldn't
> itnerfere with any other TPM functionality.

interfere

Can this be tested with QEMU somehow?

> Signed-off-by: Matthew Garrett <mjg59@google.com>
> Cc: stable@vger.kernel.org
> ---
>   drivers/char/tpm/tpm-chip.c | 4 +---
>   1 file changed, 1 insertion(+), 3 deletions(-)
> 
> diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
> index 3d6d394a8661..58073836b555 100644
> --- a/drivers/char/tpm/tpm-chip.c
> +++ b/drivers/char/tpm/tpm-chip.c
> @@ -596,9 +596,7 @@ int tpm_chip_register(struct tpm_chip *chip)
>   
>   	tpm_sysfs_add_device(chip);
>   
> -	rc = tpm_bios_log_setup(chip);
> -	if (rc != 0 && rc != -ENODEV)
> -		return rc;
> +	tpm_bios_log_setup(chip);
>   
>   	tpm_add_ppi(chip);

Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>

Kind regards,

Paul