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

From: Rafael J. Wysocki
Date: Wed Jul 04 2018 - 06:39:43 EST


On Monday, July 2, 2018 2:52:24 PM CEST Sudeep Holla wrote:
>
> On 02/07/18 12:01, Rafael J. Wysocki wrote:
> > On Mon, Jul 2, 2018 at 11:57 AM, Sudeep Holla <sudeep.holla@xxxxxxx> wrote:
> >>
> >>
> >> 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.
> >
> > So any chance to provide a Fixes: tag?
>
> Sure, since it was in the same release, I didn't add it.
>
> Fixes: 2bd00bcd73e5 ("ACPI/PPTT: Add Processor Properties Topology Table
> parsing")
>
>

Applied now, thanks!