https://bugs.kde.org/show_bug.cgi?id=526934
Bug ID: 526934
Summary: kscreenlocker_greet SIGSEGV in libPlasmaQuick after
deep suspend/resume with external monitor
Classification: Plasma
Product: plasmashell
Version First 6.7.5
Reported In:
Platform: Fedora RPMs
OS: Linux
Status: REPORTED
Severity: crash
Priority: NOR
Component: Screen locking
Assignee: [email protected]
Reporter: [email protected]
Target Milestone: 1.0
Created attachment 197010
--> https://bugs.kde.org/attachment.cgi?id=197010&action=edit
Journal logs from two reproducible kscreenlocker crashes after suspend
I'm experiencing a reproducible crash of `kscreenlocker_greet` after waking my
laptop from deep suspend.
I'm running Fedora 44 with KDE Plasma 6.7.5 on Wayland. My laptop is a Lenovo
Legion 5 with an NVIDIA RTX 3060 Laptop GPU and NVIDIA driver 610.57.04.
I normally use the laptop with its lid closed, connected to an external
DisplayPort monitor (2560x1440, 180 Hz). The internal laptop display (`eDP-1`)
is disabled.
**Steps to reproduce:**
1. Start a KDE Plasma Wayland session with the laptop lid closed and only the
external monitor enabled.
2. Suspend the system using `sudo rtcwake -m no -s 120 && sudo systemctl
suspend`.
3. Wait for the laptop to wake automatically.
4. Check the journal for screen locker crashes.
**What happens:**
The system wakes up successfully and the NVIDIA driver continues working, but
shortly after resuming, multiple KDE processes report:
`There are no outputs - creating placeholder screen`
A few seconds later, `kscreenlocker_greet` crashes with SIGSEGV in
`libPlasmaQuick.so.6.7.5`, and KWin attempts to restart the screen locker.
I reproduced this twice on October 11, 2026:
- First resume at 12:17:53, crash at 12:17:59 (PID 7241).
- Second resume at 12:33:57, crash at 12:34:03 (PID 9252).
Both crashes occurred at the same offset, `0x36fe1`, in
`libPlasmaQuick.so.6.7.5`.
Using `eu-addr2line`, I identified the function as:
`PlasmaQuick::SharedQmlEngine::rootObject() const`
KWin also reports:
`Greeter Process encountered an unhandled error: QProcess::Crashed`
`Greeter process exit unregular. Restarting lock.`
Interestingly, manually locking and unlocking the desktop with Meta+L works
normally. The crash has only occurred after resuming from suspend.
I also verified the installed KDE and Qt packages using `rpm -V`, and no
integrity issues were found.
The system previously had more serious suspend/resume problems with NVIDIA
615.71.09. Downgrading to 610.57.04 fixed the observed GPU wake-up failures,
but the screen locker crash still occurs.
**Expected behavior:**
The screen locker should recover normally after suspend, even if the external
display temporarily disappears during wake-up.
I haven't been able to obtain a full coredump, but I can provide additional
journal logs if needed.
--
You are receiving this mail because:
You are watching all bug changes.
