Im using Ubuntu 20.04 LTS and have the same problem. I got the problem after upgrading from Kernel 5.4.0-73-generic to 5.4.0-74-generic. As I got in addition a firmware/microcode update it may be possible that the error is adjacent to that update too. If I boot to kernel 5.4.0-73-generic I have access to the serial line (e.g. /dev/ttyACM3).
-- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1931684 Title: cdc_acm: acm_port_activate - usb_submit_urb(ctrl irq) failed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1931684/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
