Re: WARNING in __thermal_cooling_device_register()

[Frank Rowand]

Hi Daniel,

On 1/18/23 02:23, Daniel Lezcano wrote:
> 
> Hi Frank,
> 
> Thanks for reporting the WARNING.
> 
> It is currently being fixed:
> 
> https://lore.kernel.org/all/20230112154721.452292-1-caleb.connolly@xxxxxxxxxx/

Thanks for that pointer!

Viresh did a V4 of the patch this morning, which worked for my case.  I sent my
tested-by.

-Frank

> 
>   -- Daniel
> 
> 
> On 18/01/2023 08:38, Frank Rowand wrote:
>> I am getting two new warning traces in v6.2-rc1 on boot that are not present in v6.1-rc1.
>>
>> I have not done a bisect yet, but wanted to report the issue without further delay.
>>
>> The configuration is qcom_defconfig
>>
>> The system is a Qualcomm Dragon 8074
>>
>> I have not done any debugging, but noted some changes to the file that contains
>> __thermal_cooling_device_register() since 6.1-rc1:
>>
>> linux--6.2-rc> git log --oneline v6.1-rc1.. -- drivers/thermal/thermal_core.c
>> 4748f9687caa thermal: core: fix some possible name leaks in error paths
>> b778b4d782d4 thermal/core: Protect thermal device operations against thermal device removal
>> 05eeee2b51b4 thermal/core: Protect sysfs accesses to thermal operations with thermal zone mutex
>> 1c439dec359c thermal/core: Introduce locked version of thermal_zone_device_update
>> 30b2ae07d3d6 thermal/core: Delete device under thermal device zone lock
>> d35f29ed9d11 thermal/core: Destroy thermal zone device mutex in release function
>> e49a1e1ee078 thermal/core: fix error code in __thermal_cooling_device_register()
>> c408b3d1d9bb thermal: Validate new state in cur_state_store()
>>
>>
>>
>> The stack traces are:
>>
>> -----------[ cut here ]------------
>> WARNING: CPU: 0 PID: 31 at lib/kobject.c:718 kobject_put+0x114/0x29c
>> kobject: '(null)' ((ptrval)): is not initialized, yet kobject_put() is being called.
>> Modules linked in:
>> CPU: 0 PID: 31 Comm: kworker/u8:2 Not tainted 6.2.0-rc1 #1
>> Hardware name: Generic DT based system
>> Workqueue: events_unbound deferred_probe_work_func
>>   unwind_backtrace from show_stack+0x10/0x14
>>   show_stack from dump_stack_lvl+0x40/0x4c
>>   dump_stack_lvl from __warn+0x7c/0x15c
>>   __warn from warn_slowpath_fmt+0x98/0xcc
>>   warn_slowpath_fmt from kobject_put+0x114/0x29c
>>   kobject_put from __thermal_cooling_device_register+0x11c/0x388
>>   __thermal_cooling_device_register from __power_supply_register+0x49c/0x5dc
>>   __power_supply_register from devm_power_supply_register+0x54/0x90
>>   devm_power_supply_register from smbb_charger_probe+0x358/0x61c
>>   smbb_charger_probe from platform_probe+0x5c/0xb8
>>   platform_probe from really_probe+0xe0/0x3dc
>>   really_probe from __driver_probe_device+0x9c/0x208
>>   __driver_probe_device from driver_probe_device+0x30/0xcc
>>   driver_probe_device from __device_attach_driver+0xa8/0x120
>>   __device_attach_driver from bus_for_each_drv+0x84/0xd4
>>   bus_for_each_drv from __device_attach+0x108/0x1d8
>>   __device_attach from bus_probe_device+0x84/0x8c
>>   bus_probe_device from deferred_probe_work_func+0x9c/0xdc
>>   deferred_probe_work_func from process_one_work+0x1d4/0x510
>>   process_one_work from worker_thread+0x1fc/0x4d0
>>   worker_thread from kthread+0xf4/0x124
>>   kthread from ret_from_fork+0x14/0x2c
>> Exception stack(0xf0901fb0 to 0xf0901ff8)
>> 1fa0:                                     00000000 00000000 00000000 00000000
>> 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>> ---[ end trace 0000000000000000 ]---
>> ------------[ cut here ]------------
>> WARNING: CPU: 0 PID: 31 at lib/refcount.c:28 __thermal_cooling_device_register+0x11c/0x388
>> refcount_t: underflow; use-after-free.
>> Modules linked in:
>> CPU: 0 PID: 31 Comm: kworker/u8:2 Tainted: G        W          6.2.0-rc1 #1
>> Hardware name: Generic DT based system
>> Workqueue: events_unbound deferred_probe_work_func
>>   unwind_backtrace from show_stack+0x10/0x14
>>   show_stack from dump_stack_lvl+0x40/0x4c
>>   dump_stack_lvl from __warn+0x7c/0x15c
>>   __warn from warn_slowpath_fmt+0x98/0xcc
>>   warn_slowpath_fmt from __thermal_cooling_device_register+0x11c/0x388
>>   __thermal_cooling_device_register from __power_supply_register+0x49c/0x5dc
>>   __power_supply_register from devm_power_supply_register+0x54/0x90
>>   devm_power_supply_register from smbb_charger_probe+0x358/0x61c
>>   smbb_charger_probe from platform_probe+0x5c/0xb8
>>   platform_probe from really_probe+0xe0/0x3dc
>>   really_probe from __driver_probe_device+0x9c/0x208
>>   __driver_probe_device from driver_probe_device+0x30/0xcc
>>   driver_probe_device from __device_attach_driver+0xa8/0x120
>>   __device_attach_driver from bus_for_each_drv+0x84/0xd4
>>   bus_for_each_drv from __device_attach+0x108/0x1d8
>>   __device_attach from bus_probe_device+0x84/0x8c
>>   bus_probe_device from deferred_probe_work_func+0x9c/0xdc
>>   deferred_probe_work_func from process_one_work+0x1d4/0x510
>>   process_one_work from worker_thread+0x1fc/0x4d0
>>   worker_thread from kthread+0xf4/0x124
>>   kthread from ret_from_fork+0x14/0x2c
>> Exception stack(0xf0901fb0 to 0xf0901ff8)
>> 1fa0:                                     00000000 00000000 00000000 00000000
>> 1fc0: 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
>> 1fe0: 00000000 00000000 00000000 00000000 00000013 00000000
>> ---[ end trace 0000000000000000 ]---
>>
>>
>> -Frank
>