I am getting a kernel message spew on the console whenever I reboot one of my boxes that's equipped with a Quectel EG25-G modem:
> option1 ttyUSB0: usb_wwan_write: submit urb 0 failed: -19 When this happens, the reboot either does not complete or takes so long that it is unacceptable. It happens after the system has closed systemd-journald, so I haven't yet been able to find any additional information that might help. If I stop ModemManager for a little while before issuing the reboot, this doesn't happen. I've tried juggling the shutdown order and timing of the relevant systemd services but haven't yet found a way to put in sufficient delay for a reboot to occur reliably. My team is currently upgrading our project from Yocto's Dunfell branch to their Scarthgap branch. This takes us from Linux kernel 5.4.34 to 6.6.23, and from ModemManager 1.18.4 to 1.22. Everything worked great in the old setup. I'm not well acquainted with either body of source code (ModemManager or Linux kernel). Can anyone advise me on how I might be able to figure this out? -- Bruce Johnson Chantilly, Virginia USA
