Waybar: Upower module causes a segfault when when docking/undocking laptop

For some weeks I’ve been experiencing crashes when connecting or disconnecting my two external monitors. The crashes happen about 50% of the time.

I’m using Kanshi. When I connect my two external monitors, Kanshi puts them side by side and disables the laptop screen. When I disconnect them, Kanshi enables back the laptop screen and sets its fractional scaling to 1.4.

$ waybar -v
Waybar v0.9.13-158-g5da45ec (branch 'master')
  • Crash log. The “no modem specified” error comes from one of my custom modules I think, so just ignore it. You can also see it throwing some weird characters to the ouput way before crashing, so it might be hinting at some memory corruption going on there.
  • Coredumpctl output. I’m running the release build of Waybar with no debugging symbols, but I still show backtrace in this log. Hope it helps.

I can reproduce the same behavior even if I disable Kanshi and remove the custom modules (I’m saying this because I saw other issues that mention these as possible causes of crashes).

Let me know if you want me to provide any more logs or a coredump.


About this issue

  • Original URL
  • State: closed
  • Created 2 years ago
  • Comments: 15 (8 by maintainers)

Most upvoted comments


It’s not even a cable, but this kind of old-fashioned interface with pins under the bottom of the laptop. The charger that connects to the docking station powers everything and charges the laptop. Monitors, keyboard and all are connected to the docking station.

@ErikReider, here the full list:

"modules-left": ["sway/workspaces", "sway/window"],
"modules-center": [],
"modules-right": ["tray", "backlight", "pulseaudio", "custom/modemmanager", "network#wlan0", "network#eth0", "temperature", "upower", "clock"],

I already tried disabling the custom module, the problem was still there.