Re: [PATCH v2] ACPI / APEI: Suppress message if HEST not present

[Borislav Petkov]

On Wed, Aug 16, 2017 at 12:27:53PM +0100, Punit Agrawal wrote:
> According to the ACPI specification, firmware is not required to provide
> the Hardware Error Source Table (HEST). When HEST is not present, the
> following superfluous message is printed to the kernel boot log -
> 
> [    3.460067] GHES: HEST is not enabled!
> 
> Extend hest_disable variable to track whether the firmware provides this
> table and if it is not present skip any log output. The existing
> behaviour is preserved in all other cases.
> 
> Suggested-by: Borislav Petkov <bp@xxxxxxx>
> Signed-off-by: Punit Agrawal <punit.agrawal@xxxxxxx>
> Cc: Borislav Petkov <bp@xxxxxxx>
> Cc: James Morse <james.morse@xxxxxxx>
> ---
>  drivers/acpi/apei/ghes.c |  4 ++--
>  drivers/acpi/apei/hest.c | 13 +++++++------
>  include/acpi/apei.h      |  8 +++++++-
>  3 files changed, 16 insertions(+), 9 deletions(-)
> 
> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
> index d661d452b238..f8685bcbeff2 100644
> --- a/drivers/acpi/apei/ghes.c
> +++ b/drivers/acpi/apei/ghes.c
> @@ -1262,10 +1262,10 @@ static int __init ghes_init(void)
>  {
>  	int rc;
>  
> -	if (acpi_disabled)
> +	if (acpi_disabled || hest_disable == HEST_NOT_FOUND)
>  		return -ENODEV;
>  
> -	if (hest_disable) {
> +	if (hest_disable == HEST_DISABLED) {
>  		pr_info(GHES_PFX "HEST is not enabled!\n");
>  		return -EINVAL;
>  	}

Yap, looks good.

Just a minor nitpick: I'd additionally group the hest_disable checking
in one switch-case, so that the code flow is obvious at a quick glance:

        if (acpi_disabled)
                return -ENODEV;

        switch (hest_disable) {
        case HEST_NOT_FOUND:
                return -ENODEV;
        case HEST_DISABLED:
                pr_info(GHES_PFX "HEST is not enabled!\n");
                return -EINVAL;
        default:
                break;
        }

Thx.

-- 
Regards/Gruss,
    Boris.

SUSE Linux GmbH, GF: Felix ImendÃrffer, Jane Smithard, Graham Norton, HRB 21284 (AG NÃrnberg)
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