Kernel panic when unpluggin AC adaptor

[Giovanni Trematerra]

On Tue, May 25, 2010 at 5:52 PM, David DEMELIER
<demelier.david at gmail.com> wrote:
> 2010/5/25 Giovanni Trematerra <giovanni.trematerra at gmail.com>:
>> On Mon, May 24, 2010 at 9:43 PM, David DEMELIER
>> <demelier.david at gmail.com> wrote:
>>> 2010/5/12 Giovanni Trematerra <giovanni.trematerra at gmail.com>:
>>>> On Fri, May 7, 2010 at 8:33 PM, Demelier David <demelier.david at gmail.com> wrote:
>>>>> Le Vendredi 07 mai 2010 à 18:22 +0200, Giovanni Trematerra a écrit :
>>>>>> On Fri, May 7, 2010 at 2:08 PM, Demelier David <demelier.david at gmail.com> wrote:
>>>>>> > Hi,
>>>>>> >        I noticed that pluggin the AC adaptor when I boot without it does not
>>>>>> >        panic. It only panic when removing it.
>>>>>> >
>>>>>> >        Maybe that could help ?
>>>>>> >
>>>>>>
>>>>>> Good to know. The problem lies somewhere when performance state change.
>>>>>> In your case it happens when you remove AC adaptor. Let's hope someone on
>>>>>> acpi@ ml comes up with a good idea.
>>>>>>
>>>>>
>>>>> Okay so for the moment no change, I'll wait for someone with an idea
>>>>> that could solve my problem. For me because the panic only happens when
>>>>> changing profile from ac plugged -> ac unplugged (and not the reverse) I
>>>>> would think it's a cpu related acpi issue.
>>>>>
>>>>
>>>> I looked deeper and it seems to me that when you unplug the AC
>>>> adapter, acpi_cpu_notify calls acpi_cpu_cx_cst that try to allocate a
>>>> new cx_ptr->p_lvlx  via acpi_PkgGas.
>>>> If acpi_PkgGas set cx_ptr->p_lvlx to NULL for any reasons you'll have
>>>> the panic that you reported.
>>>> A solution would be to set acpi_cpu_hook to NULL so acpi_cpu_idle won't call it.
>>>> I need some time to have a patch because of the possible race between
>>>> acpi_cpu_notify and
>>>> acpi_cpu_idle during set acpi_cpu_hook to NULL.
>>>> if you have time and want panic your system you could try the attached
>>>> patch, just to be
>>>> sure that we catch it.
>>>>
>>>
>>> Hi, it paniced today ! I don't know why it randomly panic but it did,
>>> the backtrace didn't change. There is a picture about the panic :
>>>
>>> http://img541.imageshack.us/img541/2773/dsc00388xa.jpg
>>
>> What was you trying? acpi_idle5.diff.txt patch?
>> How did it panic? Unplugging AC adapter?
>>
>
> Hi, I tried this one : lvlx.diff.txt. Yes by unplugging the AC adapter.
>

This is an old one. Could you try acpi_idle5.diff.txt? I kept you in
Cc when I sent to
the list. If you have problems, let me know, I'll resend to you  the patch.

Thank you.

--
Gianni