systemd-udev-settle.service blocks boot for ~90s with a debug-logged assertion failure

[Dan Watkins]

I started seeing this when I booted this morning, and I've seen it in the 2 reboots since (one for a new kernel, one to capture debug logs). After modifying /etc/udev/udev.conf to capture debug logging, I see:

$ journalctl -u systemd-udev-settle.service -b0
-- Logs begin at Wed 2019-08-14 09:26:57 EDT, end at Mon 2019-10-21 11:53:56 EDT. --
Oct 21 11:42:50 surprise udevadm[678]: Assertion 's' failed at ../src/libsystemd/sd-event/sd-event.c:1688, function sd_event_source_set_description(). Ignoring.
Oct 21 11:44:24 surprise systemd[1]: Started udev Wait for Complete Device Initialization.

(Of possible value for debugging: the last time I rebooted before I was seeing this issue was on Oct 7th, so I had the 5.3.0-13-generic kernel and, looking at the publishing history, an older version of systemd too.)

ProblemType: Bug
DistroRelease: Ubuntu 19.10
Package: udev 242-7ubuntu3
ProcVersionSignature: Ubuntu 5.3.0-19.20-generic 5.3.1
Uname: Linux 5.3.0-19-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair nvidia_modeset nvidia
ApportVersion: 2.20.11-0ubuntu8
Architecture: amd64
CurrentDesktop: i3
CustomUdevRuleFiles: 70-snap.core.rules 70-snap.spotify.rules
Date: Mon Oct 21 11:50:26 2019
InstallationDate: Installed on 2019-05-07 (166 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
MachineType: Gigabyte Technology Co., Ltd. B450M DS3H
ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-5.3.0-19-generic root=/dev/mapper/ubuntu--vg-root ro quiet splash resume=UUID=73909634-a75d-42c9-8f66-a69138690756 vt.handoff=7
SourcePackage: systemd
UpgradeStatus: Upgraded to eoan on 2019-05-08 (165 days ago)
dmi.bios.date: 01/25/2019
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: F4
dmi.board.asset.tag: Default string
dmi.board.name: B450M DS3H-CF
dmi.board.vendor: Gigabyte Technology Co., Ltd.
dmi.board.version: x.x
dmi.chassis.asset.tag: Default string
dmi.chassis.type: 3
dmi.chassis.vendor: Default string
dmi.chassis.version: Default string
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvrF4:bd01/25/2019:svnGigabyteTechnologyCo.,Ltd.:pnB450MDS3H:pvrDefaultstring:rvnGigabyteTechnologyCo.,Ltd.:rnB450MDS3H-CF:rvrx.x:cvnDefaultstring:ct3:cvrDefaultstring:
dmi.product.family: Default string
dmi.product.name: B450M DS3H
dmi.product.sku: Default string
dmi.product.version: Default string
dmi.sys.vendor: Gigabyte Technology Co., Ltd.
mtime.conffile..etc.udev.udev.conf: 2019-10-21T11:39:04.067705

[Dan Streetman (ddstreet)]

please reopen if this is still an issue