Re: power-off delay/hang due to commit 6d25be57 (mainline)

From: Stephen Berman
Date: Sun Jan 24 2021 - 08:51:17 EST


On Mon, 04 Jan 2021 16:38:43 +0100 Stephen Berman <stephen.berman@xxxxxxx> wrote:

> On Thu, 31 Dec 2020 21:46:11 +0100 "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> wrote:
>
>> ATM, I'm tempted to do something like the patch below (with the rationale
>> that it shouldn't be necessary to read the temperature right after updating
>> the trip points if polling is in use, because the next update through polling
>> will cause it to be read anyway and it will trigger trip point actions as
>> needed).
>>
>> Stephen, can you give it a go, please?
>
> On Sat, 02 Jan 2021 12:03:17 +0100 "Rafael J. Wysocki" <rjw@xxxxxxxxxxxxx> wrote:
>
>> There is one more way to address this, probably better: instead of checking the
>> temperature right away in acpi_thermal_notify(), queue that on
>> acpi_thermal_pm_queue
>> and so only if another thermal check is not pending.
>>
>> This way there will be at most one temperature check coming from
>> acpi_thermal_notify() queued up at any time which should prevent the
>> build-up of work items from taking place.
>>
>> So something like this:
>
> Thanks for the patches. I'll try them as soon as I can.

FTR, since this is the thread I started for this bug, I've confirmed in
https://lore.kernel.org/lkml/87y2gi78sg.fsf@xxxxxxx/T/#t that the latest
patch fixes the bug.

Steve Berman