NRF9151DK autonomous resets when simultaneously starting LTE connection and GPS on modem FW 2.0.2

[Sebastiaan Merckx]

I have updated a board (NRF9151DK) from modem FW 2.0.1 to 2.0.2. The board is also equipped with nrf7002-EK, and the support for the wifi driver is enabled (SB_CONFIG_WIFI_NRF70, SB_CONFIG_WIFI_NRF70_SCAN_ONLY, haven't verified if this makes a difference).

The previous version of the application works fine, in which we initialize the modem at startup, and simultaneously initiate an LTE connection and activate the internal GPS. On the new 2.0.2 firmware, this simultaneous action results in an autonomous reset, which can be fixed by e.g. adding a 100msec sleep before activating the internal gps. The same problem occurs on other devkits too (observed on 2 out of 2).

I mainly want to notify you of this difference, because I'll not be the only person suffering from this. I leave it up to you to consider if a fix is possible.

I can try out alternative solutions if necessary.

Best regards,

Sebastiaan

[Sebastiaan Merckx]

I agree that it's likely an app issue, from what is described here. But I'm not new to watchdog, not new to zephyr, not new to threads, ... and I can't figure out why the watchdog fires in this case. That's why I raised the ticket in the first place. I've provided a stripped down reproduction sample. If anyone is able to point out where the mistake is (in the app), I'm happy to learn from that. But so far, my feeling is that there's a deeper issue.