Bug 217996

Summary:	Intel 7560 LTE Modem stops working after resuming from standby
Product:	Drivers	Reporter:	Martin (mwolf)
Component:	Network	Assignee:	drivers_network (drivers_network)
Status:	NEW ---
Severity:	normal	CC:	bagasdotme, davem, m.chetan.kumar, shaneparslow808
Priority:	P3
Hardware:	All
OS:	Linux
Kernel Version:	6.5	Subsystem:
Regression:	Yes	Bisected commit-id:	e4f5073d53be6cec0c654fac98372047efb66947
Attachments:	dmesg after suspend with affected kernel (6.5.6)

Description Martin 2023-10-11 14:40:33 UTC

I noticed a few days ago, after Fedora moved to Kernel 6.5, that my Intel LTE Modem was not working anymore after resuming from standby. 

The journal listed this error message multiple times:
kernel: iosm 0000:01:00.0: msg timeout

It took me a while to determine the root cause of the problem, since the modem did not work either in the following warm reboots. 
Only a shutdown revived the modem.

I did a bisection of the error and I was able to find the culprit:

[e4f5073d53be6cec0c654fac98372047efb66947] net: wwan: iosm: enable runtime pm support for 7560

Comment 1 Bagas Sanjaya 2023-10-12 09:53:23 UTC

(In reply to Martin from comment #0)
> I noticed a few days ago, after Fedora moved to Kernel 6.5, that my Intel
> LTE Modem was not working anymore after resuming from standby. 
> 
> The journal listed this error message multiple times:
> kernel: iosm 0000:01:00.0: msg timeout
> 
> It took me a while to determine the root cause of the problem, since the
> modem did not work either in the following warm reboots. 
> Only a shutdown revived the modem.
> 
> I did a bisection of the error and I was able to find the culprit:
> 
> [e4f5073d53be6cec0c654fac98372047efb66947] net: wwan: iosm: enable runtime
> pm support for 7560

Can you attach dmesg output when this issue happens?

Comment 2 Martin 2023-10-12 10:18:02 UTC

Created attachment 305206 [details]
dmesg after suspend with affected kernel (6.5.6)

I booted an affected kernel (6.5.6-1-200 from fedora repo, but Thorsten Leemhuis vanilla kernels are also affected) and sent my notebook into standby. On resume the device was gone and the error messages according "iosm" appeared.

Comment 3 Martin 2023-10-12 10:21:15 UTC

also I should mention, that if this error occurs, I am unable to shutdown my system anymore. "poweroff" does not turn the laptop off, it simply triggers a reboot, where the modem is still not functional. Only pressing the powerbutton >4 secs "resets" the device.

Comment 4 Bagas Sanjaya 2023-10-17 08:12:52 UTC

(In reply to Martin from comment #0)
> I noticed a few days ago, after Fedora moved to Kernel 6.5, that my Intel
> LTE Modem was not working anymore after resuming from standby. 
> 
> The journal listed this error message multiple times:
> kernel: iosm 0000:01:00.0: msg timeout
> 
> It took me a while to determine the root cause of the problem, since the
> modem did not work either in the following warm reboots. 
> Only a shutdown revived the modem.
> 
> I did a bisection of the error and I was able to find the culprit:
> 
> [e4f5073d53be6cec0c654fac98372047efb66947] net: wwan: iosm: enable runtime
> pm support for 7560

Hi Martin,

I have posted revert proposal at [1]. Please test.

[1]: https://lore.kernel.org/netdev/20231017080812.117892-1-bagasdotme@gmail.com/

Comment 5 Martin 2023-10-17 12:33:06 UTC

yes, that patch does the trick, thank you!

Comment 6 Bagas Sanjaya 2023-10-18 06:43:13 UTC

On 17/10/2023 19:33, bugzilla-daemon@kernel.org wrote:
> https://bugzilla.kernel.org/show_bug.cgi?id=217996
> 
> --- Comment #5 from Martin (mwolf@adiumentum.com) ---
> yes, that patch does the trick, thank you!
> 

OK, I will add your Tested-by: trailer in v2.