Re: [RFC PATCH v2 0/6] net: wwan: add NMEA port type support

[Sergey Ryazanov <ryazanov.s.a@gmail.com>]

Hi Loic, Daniele,

On 10/2/25 18:44, Loic Poulain wrote:
> On Tue, Sep 30, 2025 at 9:22 AM Daniele Palmas <dnlplm@gmail.com> wrote:
> [...]
>> diff --git a/drivers/net/wwan/wwan_hwsim.c b/drivers/net/wwan/wwan_hwsim.c
>> index a748b3ea1602..e4b1bbff9af2 100644
>> --- a/drivers/net/wwan/wwan_hwsim.c
>> +++ b/drivers/net/wwan/wwan_hwsim.c
>> @@ -236,7 +236,7 @@ static void wwan_hwsim_nmea_emul_timer(struct timer_list *t)
>>          /* 43.74754722298909 N 11.25759835922875 E in DMM format */
>>          static const unsigned int coord[4 * 2] = { 43, 44, 8528, 0,
>>                                                     11, 15, 4559, 0 };
>> -       struct wwan_hwsim_port *port = from_timer(port, t, nmea_emul.timer);
>> +       struct wwan_hwsim_port *port = timer_container_of(port, t,
>> nmea_emul.timer);
>>
>> it's basically working fine in operative mode though there's an issue
>> at the host shutdown, not able to properly terminate.
>>
>> Unfortunately I was not able to gather useful text logs besides the picture at
>>
>> https://drive.google.com/file/d/13ObWikuiMMUENl2aZerzxFBg57OB1KNj/view?usp=sharing
>>
>> showing an oops with the following call stack:
>>
>> __simple_recursive_removal
>> preempt_count_add
>> __pfx_remove_one
>> wwan_remove_port
>> mhi_wwan_ctrl_remove
>> mhi_driver_remove
>> device_remove
>> device_del
>>
>> but the issue is systematic. Any idea?
>>
>> At the moment I don't have the time to debug this deeper, I don't even
>> exclude the chance that it could be somehow related to the modem. I
>> would like to further look at this, but I'm not sure exactly when I
>> can....
> 
> Thanks a lot for testing, Sergey, do you know what is wrong with port removal?

Daniele, thanks a lot for verifying the proposal on a real hardware and 
sharing the build fix.

Unfortunately, I unable to reproduce the crash. I have tried multiple 
times to reboot a VM running the simulator module even with opened GNSS 
device. No luck. It reboots and shutdowns smoothly.

--
Sergey