Re: [PATCH] ACPI/PPTT: use ACPI ID whenever ACPI_PPTT_ACPI_PROCESSOR_ID_VALID is set

From: Sudeep Holla
Date: Mon Jul 02 2018 - 05:58:03 EST




On 02/07/18 10:06, Rafael J. Wysocki wrote:
> On Fri, Jun 29, 2018 at 6:17 PM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
>> Currently we use the ACPI processor ID only for the leaf/processor nodes
>> as the specification states it must match the value of ACPI processor ID
>> field in the processorâs entry in the MADT.
>>
>> However, if a PPTT structure represents processors group, it match a
>> processor container UID in the namespace and ACPI_PPTT_ACPI_PROCESSOR_ID_VALID
>> flag describe whether the ACPI processor ID is valid.
>>
>> Lets use UID whenever ACPI_PPTT_ACPI_PROCESSOR_ID_VALID is set to be
>> consistent instead of using table offset as it's currently done for non
>> leaf nodes.
>>
>> Cc: "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx>
>> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
>> ---
>> drivers/acpi/pptt.c | 10 ++++++++--
>> 1 file changed, 8 insertions(+), 2 deletions(-)
>>
>> Hi,
>>
>> There's ongoing discussion on assigning ID based in OS using simple
>> counters. It can never be consistent with firmware's view. So if the
>> firmware provides valid UID for non-processors node, we must use it.
>
> OK
>
> Do you regard this as a fix for the recently merged PPTT material? If
> so, I should apply it as a fix for 4.18.
>

Yes, it should be considered as fix IMO.

--
Regards,
Sudeep