Re: [REGRESSION 4.17] Spurious wakeup / reboot with power button

Takashi Iwai
2018-07-05T16:56:37Z

On Thu, 05 Jul 2018 18:02:11 +0200,
Rafael J. Wysocki wrote:
>
> [The Lv's address is not valid any more, so drop it from the CC]
>
> On Thursday, July 5, 2018 5:10:20 PM CEST Rafael J. Wysocki wrote:
> > On Thu, Jul 5, 2018 at 5:09 PM, Takashi Iwai <tiwai@suse.de> wrote:
> > > On Thu, 05 Jul 2018 16:00:14 +0200,
> > > Thomas H4nig wrote:
> > >>
> > >> Am 05.07.2018 um 14:12 schrieb Takashi Iwai:
> > >> > On Thu, 05 Jul 2018 12:41:03 +0200,
> > >> > Rafael J. Wysocki wrote:
> > >> >>
> > >> >> On Thursday, July 5, 2018 11:50:11 AM CEST Takashi Iwai wrote:
> > >> >>> On Thu, 05 Jul 2018 11:34:59 +0200,
> > >> >>> Rafael J. Wysocki wrote:
> > >> >>>>
> > >> >>>> Hi,
> > >> >>>>
> > >> >>>> On Thu, Jul 5, 2018 at 9:05 AM, Takashi Iwai <tiwai@suse.de> wrote:
> > >> >>>>> Hi,
> > >> >>>>>
> > >> >>>>> we've got a regression report since 4.17 about the behavior of
> > >> >>>>> power-off with the power button. When a machine is powered off with
> > >> >>>>> the power button on desktop, it reboots after a few seconds instead of
> > >> >>>>> power down.
> > >> >>>>>
> > >> >>>>> The manual power down via "systemctl poweroff" works fine, so it's
> > >> >>>>> possibly some spurious wakeup by the power button action, and some
> > >> >>>>> ACPI-related change is suspected.
> > >> >>>>> The regression still remains in 4.18-rc3.
> > >> >>>>
> > >> >>>> There are only a few ACPI commits directly related to power management
> > >> >>>> between 4.16 and 4.17 and none of them looks particularly suspicious.
> > >> >>>
> > >> >>> OK, interesting.
> > >> >>>
> > >> >>>> It looks like the power button state may not be cleared sufficiently
> > >> >>>> after it's been pressed which is now visible for some reason.
> > >> >>>
> > >> >>> Hmm, where can such a state remain? Since it happens after the
> > >> >>> machine turned off, some (ACPI) wakeup bits?
> > >> >>
> > >> >> Basically, yes.
> > >> >>
> > >> >> It looks like a GPE may remain active which then triggers wakeup after
> > >> >> shutdown.
> > >> >>
> > >> >> On a hunch, I'm wondering if reverting commit
> > >> >>
> > >> >> 18996f2db918 ACPICA: Events: Stop unconditionally clearing ACPI IRQs during suspend/resume
> > >> >>
> > >> >> (may not revert clearly, though) makes any difference.
> > >> >
> > >> > OK, I'm building a 4.17.x test kernel with that revert, in OBS
> > >> > home:tiwai:bsc1099930 repo.
> > >> >
> > >> > Thomas, could you try later the kernel in
> > >> > http://download.opensuse.org/repositories/home:/tiwai:/bsc1099930/standard/
> > >> > ? It'll take an hour or so until the build finishes.
> > >>
> > >> With your new built kernel
> > >> 4.17.4-1.g6f23755-default
> > >>
> > >> the power button works again, so the revert solved the problem
> > >
> > > Thanks, that clarifies the cause.
> > > Adding Erik and Lv to Cc.
> > >
> > > I guess it's the side-effect by removing
> > > acpi_ev_walk_gpe_list(acpi_hw_clear_gpe_block, NULL);
> > > in acpi_hw_disable_all_gpes().
> > >
> > > This function is called from acpi_power_off_prepare(), and the machine
> > > goes to power off without clearing the GPEs, hence it's woken up later
> > > unexpectedly.
> >
> > That's correct.
> >
> > We need to fix up that commit. I'll try to prepare something.
> >
>
> Below is a patch to test that theory and maybe fix things if it is correct.
>
> What it does is to clear all GPEs after disabling them in
> acpi_power_off_prepare() which should address the issue if our theory
> about the underlying reason is correct.
>
> Please test.

OK, building a new test kernel package in OBS home:tiwai:bsc1099930-2
repo. It'll appear at
http://download.opensuse.org/repositories/home:/tiwai:/bsc1099930-2/standard/

Thomas, please give it a try later.

thanks,

Takashi