Re: [PATCH 07/14 v3] bq27x00: Cache battery registers

[Lars-Peter Clausen]

On 02/21/2011 03:00 PM, Grazvydas Ignotas wrote:
>>> However there is bigger problem, compiling as module and doing
>>> insmod/rmmod/insmod causes kernel OOPS:
>>>
>>> [  882.575714] BUG: sleeping function called from invalid context at
>>> arch/arm/mm/fault.c:295
>>> [  882.584350] in_atomic(): 0, irqs_disabled(): 128, pid: 1154, name: insmod
>>> ...
>>> [  882.959930] Unable to handle kernel NULL pointer dereference at
>>> virtual address 00000000
>>> [  882.968444] pgd = c14c8000
>>> [  882.977905] Internal error: Oops: 817 [#1]
>>> ...
>>> [  883.304412] [<c007eed8>] (__queue_work+0x140/0x260) from
>>> [<c007f044>] (queue_work_on+0x2c/0x34)
>>> [  883.313568] [<c007f044>] (queue_work_on+0x2c/0x34) from
>>> [<bf008390>] (bq27x00_update+0x1f8/0x220 [bq27x00_battery])
>>> [  883.324584] [<bf008390>] (bq27x00_update+0x1f8/0x220
>>> [bq27x00_battery]) from [<bf0084c8>] (bq27x00_battery_poll+0x14/0x48
>>> [bq27x00_battery])
>>>
>>> full backtrace attached.
>>
>> I can't reproduce that OOPS. And the backtrace looks a bit strange,
>> queue_work_on is not called from bq27x00_update.
>> Can you send me the disassembly of your bq27x00_update?
> 
> It comes from power_supply_changed, probably omitted because
> queue_work is a tail function of power_supply_changed. It's probably
> something i2c specific, I could try bisecting it for you if you like,
> I know it doesn't happen before this series.

Hi

The following patch should hopefully fix the issue.

- Lars