kde plasma hangs on reboot, plasma-plasmashell timeout error

System hangs during shutdown. plasma-plasmashell times out because the default stop timeout is 5 seconds. KDE needs more time. Increase it to 30 seconds.

July 24, 2026 · 4 min

Reboot the system. It hangs. Doesn’t crash, doesn’t give an error on screen, just sits there for what feels like forever. Eventually it times out and reboots anyway. But every single reboot does this.

Check the logs and you see this:

plasma-plasmashell.service: State 'stop-sigterm' timed out. Aborting.
plasma-plasmashell.service: Failed with result 'timeout'.

KDE Plasma is not shutting down in time. The system gives it a timeout to close gracefully, and Plasma needs more time than that timeout allows.

understanding the problem

When you reboot or shut down, systemd stops all running services. It sends a SIGTERM signal (like saying “please stop”) and waits for the service to exit. If the service does not exit within the timeout period, systemd kills it with SIGKILL (forceful kill).

Plasma-plasmashell is the main KDE Plasma window manager. When it gets SIGTERM, it needs to clean up. Close open windows. Save state. Sync data. All of that takes time. On modern systems with lots of open applications, this can easily take more than 5 seconds.

Your system was set to DefaultTimeoutStopSec=5s. That is the timeout for all system services. Five seconds is too short for Plasma. So Plasma gets killed mid-shutdown, and the system has to force a reboot.

checking your current state

Look at your systemd config:

grep DefaultTimeoutStopSec /etc/systemd/system.conf

If you see 5s or anything less than 10s, that is your problem.

Check the journal when it happens:

sudo journalctl -b -1 | grep -i "timeout\|plasma-plasmashell"

Should show plasma-plasmashell timing out during shutdown.

my situation

I had set DefaultTimeoutStopSec=5s to debug something else. Did not realize Plasma needs more time. Every reboot hung waiting for Plasma to exit. After 5 seconds, systemd gave up and killed it anyway.

the fix

Increase the timeout to 30 seconds. That gives Plasma and other services plenty of time to shut down gracefully:

sudo sed -i 's/DefaultTimeoutStopSec=5s/DefaultTimeoutStopSec=30s/' /etc/systemd/system.conf

Verify it:

grep DefaultTimeoutStopSec /etc/systemd/system.conf

Should show:

DefaultTimeoutStopSec=30s

Reload the systemd manager to apply the change:

sudo systemctl daemon-reload

Then reboot:

sudo systemctl reboot

Plasma will now shut down cleanly without hanging. It has 30 seconds instead of 5. That is more than enough time.

why this works

Plasma is not broken. It is not hanging. It is just a slow shutdown. KDE cleans up widgets, closes applications, saves session state. All of this takes time. Thirty seconds gives it breathing room to do all that without systemd killing it.

The default timeout on fresh Fedora installs is usually 90 seconds. I had manually lowered it to 5 seconds for troubleshooting. Forgot to raise it back. Plasma got caught in the middle.

why the timeout exists

Systemd has a timeout because otherwise a misbehaving service could hang forever and the system would never shut down. The timeout is there to prevent that. But it needs to be long enough for normal services to clean up properly. Thirty seconds is reasonable for most things, including Plasma.

testing it

After rebooting, watch the shutdown sequence. You should not see any timeout messages for plasma-plasmashell. The system should reboot cleanly without hanging.

Check the next boot logs to confirm:

sudo journalctl -b -1 | grep -i "plasma-plasmashell\|timeout"

Should not show timeout for Plasma. If it does, increase the timeout to 45 or 60 seconds.

what not to do

Do not set the timeout to 0 or disabled. That removes the protection against hung services. Leave it at 30 or higher, but not disabled.

Do not kill Plasma manually during shutdown. The timeout mechanism is there for a reason. Let it shut down on its own.

Do not ignore the problem hoping it will go away. Hanging on every reboot is annoying and can cause data loss if you hard reboot.

takeaway

KDE Plasma takes more than 5 seconds to shut down gracefully. If your DefaultTimeoutStopSec is too low, Plasma gets killed before it finishes. Increase the timeout to 30 seconds. Plasma will exit cleanly and your reboots will work properly.

This applies to any heavy application. GUI applications, database servers, anything that needs time to clean up. If you see timeout messages for any service, increase the timeout and that service should behave properly.