adding dmesg log of the OOOPS note that the behavior differs from bug #1905782 on Ubuntu 18.
On Ubuntu 18 no OOPS is triggered, instead the driver enters an endless loop when the USB device gets disconnected later On Ubuntu 20 a kernel OOPS is generated and takes the whole USB stack with it. past that point no more USB events are generated and the system doesn't even notice USB devices getting plugged in or plugged out. note that to trigger the OOOPS I had to repeat the procedure to reproduce twice - connect, try to set dtr/rts, disconnect, connect again, once more try to set dtr/rts --> OOOPS on Ubuntu18 the modemmanager service automatically tried to set dtr/rts on the device. On Ubuntu 20 I had to do this by hand by opening the tty device with: minicom -o -D /dev/ttyACM0 ** Attachment added: "dmesg2.log" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1905994/+attachment/5438802/+files/dmesg2.log -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1905994 Title: failure to set dtr/rts on USB VCP causes kernel page fault To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1905994/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
