Re: [PATCH v2] acpi: Fix HED module initialization order when it is built-in

[Xiaofei Tan <tanxiaofei@huawei.com>]

在 2025/1/15 23:51, Rafael J. Wysocki 写道:
> On Wed, Jan 15, 2025 at 1:38 PM Xiaofei Tan <tanxiaofei@huawei.com> wrote:
>> When the module HED is built-in, the init order is determined by
>> Makefile order. That order violates expectations. Because the module
>> HED init is behind evged. RAS records can't be handled in the
>> special time window that evged has initialized while HED not.
>> If the number of such RAS records is more than the APEI HEST error
>> source number, the HEST resources could be occupied all, and then
>> could affect subsequent RAS error reporting.
>>
>> If build HED as a module, the problem remains. To solve this problem
>> completely, change the ACPI_HED from tristate to bool.
>>
>> Reviewed-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>
>> Signed-off-by: Xiaofei Tan <tanxiaofei@huawei.com>
>> ---
>>   drivers/acpi/Kconfig  | 2 +-
>>   drivers/acpi/Makefile | 8 +++++++-
>>   2 files changed, 8 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/acpi/Kconfig b/drivers/acpi/Kconfig
>> index d81b55f5068c..7f10aa38269d 100644
>> --- a/drivers/acpi/Kconfig
>> +++ b/drivers/acpi/Kconfig
>> @@ -452,7 +452,7 @@ config ACPI_SBS
>>            the modules will be called sbs and sbshc.
>>
>>   config ACPI_HED
>> -       tristate "Hardware Error Device"
>> +       bool "Hardware Error Device"
>>          help
>>            This driver supports the Hardware Error Device (PNP0C33),
>>            which is used to report some hardware errors notified via
>> diff --git a/drivers/acpi/Makefile b/drivers/acpi/Makefile
>> index 40208a0f5dfb..b50d1baeb71f 100644
>> --- a/drivers/acpi/Makefile
>> +++ b/drivers/acpi/Makefile
>> @@ -15,6 +15,13 @@ endif
>>
>>   obj-$(CONFIG_ACPI)             += tables.o
>>
>> +#
>> +# The hed.o needs to be in front of evged.o to avoid the problem that
>> +# RAS errors cannot be handled in the special time window of startup
>> +# phase that evged has initialized while hed not.
>> +#
>> +obj-$(CONFIG_ACPI_HED)         += hed.o
>> +
> I'm not sure why you are insisting on this Makefile ordering change.
>
> It would be much more robust to run the hed driver init at a different
> initcall level than evged.
>
> If there is a problem with this approach, it needs to be mentioned in
> the changelog or in the comment above.

Hi Rafael，

The approach of changing the initcall level can work too.  Will send v3 patch later, thanks.


>>   #
>>   # ACPI Core Subsystem (Interpreter)
>>   #
>> @@ -95,7 +102,6 @@ obj-$(CONFIG_ACPI_HOTPLUG_IOAPIC) += ioapic.o
>>   obj-$(CONFIG_ACPI_BATTERY)     += battery.o
>>   obj-$(CONFIG_ACPI_SBS)         += sbshc.o
>>   obj-$(CONFIG_ACPI_SBS)         += sbs.o
>> -obj-$(CONFIG_ACPI_HED)         += hed.o
>>   obj-$(CONFIG_ACPI_EC_DEBUGFS)  += ec_sys.o
>>   obj-$(CONFIG_ACPI_BGRT)                += bgrt.o
>>   obj-$(CONFIG_ACPI_CPPC_LIB)    += cppc_acpi.o
>> --
> .