Re: [PATCH v6 3/7] acpi: apei: remove the unused code

gengdongjiu
2017-09-04T11:43:59Z

Hi James,

On 2017/9/1 1:50, James Morse wrote:
> Hi Dongjiu Geng,
>
> On 28/08/17 11:38, Dongjiu Geng wrote:
>> In current code logic, the two functions ghes_sea_add() and
>> ghes_sea_remove() are only called when CONFIG_ACPI_APEI_SEA
>> is defined. If not, it will return errors in the ghes_probe()
>> and not contiue. Hence, remove the unnecessary handling when
>> CONFIG_ACPI_APEI_SEI is not defined.
>
> This doesn't match what the patch does. I get this feeling this is needed for
> some future patch you haven't included.

James, let check the code, when the ghes_probe, if the CONFIG_ACPI_APEI_SEA is not defined.
it will return -ENOTSUPP and goto error, and the ghes_sea_add has no chance to execute.
similar, if the probe is failed, it should not have chance to execute ghes_sea_remove.

static int ghes_probe(struct platform_device *ghes_dev)
{
struct acpi_hest_generic *generic;
struct ghes *ghes = NULL;

int rc = -EINVAL;

generic = *(struct acpi_hest_generic **)ghes_dev->dev.platform_data;
if (!generic->enabled)
return -ENODEV;

switch (generic->notify.type) {
case ACPI_HEST_NOTIFY_POLLED:
case ACPI_HEST_NOTIFY_EXTERNAL:
case ACPI_HEST_NOTIFY_SCI:
case ACPI_HEST_NOTIFY_GSIV:
case ACPI_HEST_NOTIFY_GPIO:
break;

case ACPI_HEST_NOTIFY_SEA:
if (!IS_ENABLED(CONFIG_ACPI_APEI_SEA)) {
pr_warn(GHES_PFX "Generic hardware error source: %d notified via SEA is not supported\n",
generic->header.source_id);
rc = -ENOTSUPP;
goto err;
}
break;

>
>
>> change since v5:
>> 1. remove the SEI notification type handling, because the SEI is
>> asynchronous exception and the address is not accurate. so
>> not call memory_failure() to handle it.
>
> Setting NOTIFY_SEI as the GHES entry's notification type means the OS should
> check the GHES->ErrorStatusAddress for CPER records when it receives an
> SError-Interrupt, as it may be a notification of an error from this error source.
previously I added the NOTIFY_SEI support, but consider the error address in CPER is not accurate and calling memory_failure() may not make sense.
so I remove it.

>
> If you aren't handling the notification, why is this is in the HEST at all?
> (and if its not: its not firmware-first)
For the SEI notification, may be we can parse and handle the CPER record other than the Error physical address

>
>
> James
>
>
>> diff --git a/drivers/acpi/apei/ghes.c b/drivers/acpi/apei/ghes.c
>> index d661d452b238..c15a08db2c7c 100644
>> --- a/drivers/acpi/apei/ghes.c
>> +++ b/drivers/acpi/apei/ghes.c
>> @@ -813,7 +813,6 @@ static struct notifier_block ghes_notifier_hed = {
>> .notifier_call = ghes_notify_hed,
>> };
>>
>> -#ifdef CONFIG_ACPI_APEI_SEA
>> static LIST_HEAD(ghes_sea);
>>
>> /*
>> @@ -848,19 +847,6 @@ static void ghes_sea_remove(struct ghes *ghes)
>> mutex_unlock(&ghes_list_mutex);
>> synchronize_rcu();
>> }
>> -#else /* CONFIG_ACPI_APEI_SEA */
>> -static inline void ghes_sea_add(struct ghes *ghes)
>> -{
>> - pr_err(GHES_PFX "ID: %d, trying to add SEA notification which is not
> supported\n",
>> - ghes->generic->header.source_id);
>> -}
>> -
>> -static inline void ghes_sea_remove(struct ghes *ghes)
>> -{
>> - pr_err(GHES_PFX "ID: %d, trying to remove SEA notification which is not
> supported\n",
>> - ghes->generic->header.source_id);
>> -}
>> -#endif /* CONFIG_ACPI_APEI_SEA */
>>
>> #ifdef CONFIG_HAVE_ACPI_APEI_NMI
>> /*
>>
>
>
> .
>