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

From: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
To: Matthew Garrett <matthewgarrett@google.com>,
	linux-integrity@vger.kernel.org
Cc: Matthew Garrett <mjg59@google.com>, stable@vger.kernel.org
Subject: Re: [PATCH] tpm: Don't make log failures fatal
Date: Tue, 17 Dec 2019 12:54:35 +0200	[thread overview]
Message-ID: <71bb3bdebe302fcc8254ba9e8b607001bb87aa1b.camel@linux.intel.com> (raw)
In-Reply-To: <20191213225748.11256-1-matthewgarrett@google.com>

On Fri, 2019-12-13 at 14:57 -0800, Matthew Garrett wrote:
> 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.
> 
> Signed-off-by: Matthew Garrett <mjg59@google.com>
> Cc: stable@vger.kernel.org

Otherwise looks great but maybe it would make sense to change
tpm_bios_log_setup() as void as part of the change?

> ---
>  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);
>  

/Jarkko