Re: ACPI: EC: GPE storm detected, transactions will use polling mode

From: Rafael J. Wysocki
Date: Sat Nov 15 2008 - 14:15:17 EST


On Saturday, 15 of November 2008, Justin Mattock wrote:
> On Sat, Nov 15, 2008 at 4:06 AM, Alan Jenkins
> <alan-jenkins@xxxxxxxxxxxxxx> wrote:
> > Rafael J. Wysocki wrote:
> >>
> >> On Saturday, 15 of November 2008, Alan Jenkins wrote:
> >>
> >>>
> >>> On Sat, Nov 15, 2008 at 9:23 AM, Alexey Starikovskiy <aystarik@xxxxxxxxx>
> >>> wrote:
> >>>
> >>>>
> >>>> Andrew Morton wrote:
> >>>>
> >>>>>
> >>>>> (cc linux-acpi)
> >>>>>
> >>>>> On Fri, 14 Nov 2008 20:16:17 -0800 "Justin P. Mattock"
> >>>>> <justinmattock@xxxxxxxxx> wrote:
> >>>>>
> >>>>>
> >>>>>>
> >>>>>> just pulled the latest git today and am now noticing
> >>>>>> the lovely gpe storm being triggered.(dmesg below);
> >>>>>>
> >>>>>
> >>>>> Are any other effects observeable?
> >>>>>
> >>>>> I assume that 2.6.27 didn't do this.
> >>>>>
> >>>>>
> >>>>
> >>>> It did. Justin even opened a bug -- #11724.
> >>>>
> >>>
> >>> In case anyone else tries to follow that, it's actually #10724 :).
> >>>
> >>
> >> Yes, the "transaction in interrupt context" patch fixed that IIRC and the
> >> one
> >> of the patches in the recet ACPI merge broke it again.
> >>
> >> Justin, can you see if reverting one or more of the following commits
> >> helps:
> >>
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=8517934ef6aaa28d6e055b98df65b31cedbd1372
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=06cf7d3c7af902939cd1754abcafb2464060cba8
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=0b7084ac67fb84f0cf2f8bc02d7e0dea8521dd2d
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=a2f93aeadf97e870ff385030633a73e21146815d
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=dd15f8c42af09031e27da5b4d697ce925511f2e1
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=f8248434e6a11d7cd314281be3b39bbcf82fc243
> >>
> >> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=1cfe62c8010ac56e1bd3827e30386a87cc2f3594
> >>
> >> (please revert in this order)?
> >>
> >
> > Be aware there's a real possibility this was only a cosmetic fix (and
> > regression).
> >
> > I think the original GPE storm avoidance printed that message by default.
> > Then the "transaction in interrupt context" made the message into a
> > pr_debug(), - i.e. disabled it by default. And then my "make messages more
> > useful when GPE storm is detected" re-enabled it.
> >
> > IIRC, this flip-flopping is contained within 2.6.28-rc. I.e. I don't think
> > it will show up as a (cosmetic) regression when jumping straight from 2.6.27
> > to 2.6.28. Though I suspect it will shows up between certain versions of
> > -stable.
> >
> > Regards
> > Alan
> >
>
> O.K. I think I was wrong about stating
> this was not caused by the discharging and charging of the battery.
> to retrace my steps
> yesterday I pulled, then recompiled, then
> let the system idle for a few, then once I moved the computer to the
> other room,(unplugged/plugged the A/C adapter)
> the light turned orange on the A/C adapter then once
> the battery became fully charged(green light on A/C adapter)
> the gpe storm was triggered. Once I saw the gpe storm, I rebooted
> (under the impression the battery was in a good state),
> instantly the gpe storm was triggered. leading me
> to beleive this was something else.
> So after seeing that and sending a post I used the
> acpi_osi=Darwin option sat had a beer and worried about it tomorrow.
> Now when I woke up, and saw the commits from rafael(thanks for the help)
> I decided to make sure this was reproducible, So removing the acpi_osi option,
> then let the system idled. To my amazement the
> gpe storm was not triggered at all.
> (even unplugging and plugging the A/C multiple times had no effect)
> After a while thinking what the hell is going on here, I decided to discharge
> the battery to around 97% or 5 min. and then charge to see if this
> triggers the gpe storm. Well sure enough it did.(attached is dmesg);
>
> So for now should I go and individually revert the commits; charge,
> and discharge
> to locate the culprit, or is this something completely different?

Well, you have only one
"ACPI: EC: GPE storm detected, transactions will use polling mode" message in
the log, so the EC code seems to work as expected and you _really_ have an
interrupt storm that is worked around.

Not sure what's causing it to happen, though.

Thanks,
Rafael
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