Created attachment 1111983 [details] Small C program which demonstrates the problem. Description of problem: When I boot my system having the USB printer already attached I see the following error messages in syslog: udev-configure-printer[1339]: add usb-003-005 udev-configure-printer[1339]: device devpath is /devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1.6 udev-configure-printer[1339]: udev_enumerate_scan_devices failed The root cause is in systemd's libudev: https://github.com/systemd/systemd/commit/9a9c7dc2cbbe3c26cfbbcb02475d95ff3afe507e At least in version 222, udev_enumerate_scan_devices() does not work properly together with udev_enumerate_add_match_parent(). Version-Release number of selected component (if applicable): systemd-libs-222-10.fc23.x86_64 How reproducible: 100% Steps to reproduce: - either have a supported USB printer attached at bootup or alternatively use the attached test program to check for the API misbehaviour: 1. gcc -Wall -o udev_test udev_test.c -ludev 2. ./udev_test /sys/bus/usb/devices/3-1.6 Actual results: udev scan_devices returned: -2 Expected results: Device Path: /sys/devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1.6 Device Path: /sys/devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1.6/3-1.6:1.0 Device Path: /sys/devices/pci0000:00/0000:00:1a.0/usb3/3-1/3-1.6/3-1.6:1.0/usbmisc/lp0 Additional info: The bug is already fixed in systemd-228: https://github.com/systemd/systemd/commit/9a9c7dc2cbbe3c26cfbbcb02475d95ff3afe507e Please consider to cherry-pick this commit also for Fedora 23.
systemd-222-12.fc23 has been submitted as an update to Fedora 23. https://bodhi.fedoraproject.org/updates/FEDORA-2016-aae4b3b916
systemd-222-12.fc23 has been pushed to the Fedora 23 testing repository. If problems still persist, please make note of it in this bug report. See https://fedoraproject.org/wiki/QA:Updates_Testing for instructions on how to install test updates. You can provide feedback for this update here: https://bodhi.fedoraproject.org/updates/FEDORA-2016-aae4b3b916
systemd-222-12.fc23 has been pushed to the Fedora 23 stable repository. If problems still persist, please make note of it in this bug report.