I suspect the log lines with '"../osd": no such directory' aren't relevant here, since I see those under 6.9.1-1 too - including on a system which has never had 6.9.1-2 and has never had this lockscreen issue.

I have had even more severe problems after updating to qt6-qtwayland-0:6.9.1-2.
Almost every application crashes on startup (including the crash reporter, and frequently the plasma shell itself).

I cannot downgrade either:
> sudo dnf downgrade qt6-qtwayland
> Updating and loading repositories:
> Repositories loaded.
> Failed to resolve the transaction:
> Problem: problem with installed package
>   - installed package plasma-discover-kns-6.4.1-1.fc42.x86_64 requires libQt6Core.so.6(Qt_6.9)(64bit), but none of the providers can be installed
>   - package plasma-discover-kns-6.4.1-1.fc42.x86_64 from updates requires libQt6Core.so.6(Qt_6.9)(64bit), but none of the providers can be installed
>   - cannot install both qt6-qtbase-6.8.2-3.fc42.x86_64 from fedora and qt6-qtbase-6.9.1-1.fc42.x86_64 from @System
>   - cannot install both qt6-qtbase-6.8.2-3.fc42.x86_64 from fedora and qt6-qtbase-6.9.1-1.fc42.x86_64 from updates
>   - package qt6-qtwayland-6.8.2-1.fc42.x86_64 from fedora requires qt6-qtbase(x86-64) = 6.8.2, but none of the providers can be installed
>   - package qt6-qtwayland-6.8.2-1.fc42.x86_64 from fedora requires libQt6Core.so.6(Qt_6.8_PRIVATE_API)(64bit), but none of the providers can be installed
>   - conflicting requests
> You can try to add to command line:
>   --skip-broken to skip uninstallable packages

I'm not brave enough to try the --skip-broken option.
I had to install plasma-workspace-x11 and use the X11 session to get a functional System back.

The following are some related reports:
https://retrace.fedoraproject.org/faf/reports/1245634/
https://retrace.fedoraproject.org/faf/reports/1245856/

Thank you for your time :)

(In reply to Thomas Hepp from comment #2)
> I have had even more severe problems after updating to
> qt6-qtwayland-0:6.9.1-2.
> Almost every application crashes on startup (including the crash reporter,
> and frequently the plasma shell itself).
> 
> I cannot downgrade either:
> > sudo dnf downgrade qt6-qtwayland
> > Updating and loading repositories:
> > Repositories loaded.
> > Failed to resolve the transaction:
> > Problem: problem with installed package
> >   - installed package plasma-discover-kns-6.4.1-1.fc42.x86_64 requires libQt6Core.so.6(Qt_6.9)(64bit), but none of the providers can be installed
> >   - package plasma-discover-kns-6.4.1-1.fc42.x86_64 from updates requires libQt6Core.so.6(Qt_6.9)(64bit), but none of the providers can be installed
> >   - cannot install both qt6-qtbase-6.8.2-3.fc42.x86_64 from fedora and qt6-qtbase-6.9.1-1.fc42.x86_64 from @System
> >   - cannot install both qt6-qtbase-6.8.2-3.fc42.x86_64 from fedora and qt6-qtbase-6.9.1-1.fc42.x86_64 from updates
> >   - package qt6-qtwayland-6.8.2-1.fc42.x86_64 from fedora requires qt6-qtbase(x86-64) = 6.8.2, but none of the providers can be installed
> >   - package qt6-qtwayland-6.8.2-1.fc42.x86_64 from fedora requires libQt6Core.so.6(Qt_6.8_PRIVATE_API)(64bit), but none of the providers can be installed
> >   - conflicting requests
> > You can try to add to command line:
> >   --skip-broken to skip uninstallable packages
> 
> I'm not brave enough to try the --skip-broken option.
> I had to install plasma-workspace-x11 and use the X11 session to get a
> functional System back.
> 
> The following are some related reports:
> https://retrace.fedoraproject.org/faf/reports/1245634/
> https://retrace.fedoraproject.org/faf/reports/1245856/
> 
> Thank you for your time :)

You can downgrade safely with this oneliner without 'dnf downgrade':

sudo dnf in koji && cd $(mktemp -d) && pwd && koji download-build -a noarch -a $(uname -m) qt6-qtwayland-6.9.1-1.fc42 && sudo dnf in ./qt6-qtwayland-6.9.1-1.fc42.*.rpm

Worked for me, system is stable again

Or downgrading using the archive repos is also an option:

sudo dnf install fedora-repos-archive
sudo dnf config-manager setopt updates-archive.enabled=0
sudo dnf downgrade qt6-qtwayland-6.9.1-1.fc42 --enablerepo updates-archive

Lifesaver!
I could downgrade with the fedora-repos-archive, and the problems disappeared.
Thank you!

Downgraded with the help of koji above and lockscreen works again for me as well

Thanks, was also affected, dmesg was showing a segfault :
kscreenlocker_g[26873]: segfault at 24bc ip 00007fa97386019d sp 00007fff3cfd5370 error 4 in libLayerShellQtInterface.so.6.4.1[319d,7fa97385d000+7000]
Koji workaround applied. Thanks Szymon !

Upgraded severity to "Urgent" based on reports of impacts beyond the lockscreen (for example Thomas Hepp's here, and this user's on the KDE forum: https://discuss.kde.org/t/all-kde-apps-crash-upon-opening-interacting/36294/3).

Please, make this go away! - I was hit by this, reported in Fedora, found this thread, did the downgrade, and now System Settings don't start here. (My workaround was "Never" for the screen locker, and now I can't get it back to lock the screen.)

(In reply to pg_tips from comment #4)
> Or downgrading using the archive repos is also an option:
> 
> sudo dnf install fedora-repos-archive
> sudo dnf config-manager setopt updates-archive.enabled=0
> sudo dnf downgrade qt6-qtwayland-6.9.1-1.fc42 --enablerepo updates-archive

1. TEMPORARY SOLUTION

Downgrading using the archive repos fixed the issue for me as well:

sudo dnf install fedora-repos-archive
sudo dnf config-manager setopt updates-archive.enabled=0
sudo dnf downgrade qt6-qtwayland-6.9.1-1.fc42 --enablerepo updates-archive

Thank you @pg_tips !

2. ANNOYING SOLUTION

Also can confirm that the CTRL+ALT+F3 worked, the error instruction message said F1 but that one didn't work for me. This worked to get back to my desktop:

CTRL+ALT+F3
loginctl unlock-session 2
CTRL+D
CTRL+ALT+F2

3. MY SYSTEM INFO

Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.1
KDE Frameworks Version: 6.15.0
Qt Version: 6.9.1
Kernel Version: 6.15.3-200.fc42.x86_64 (64-bit)

(In reply to tttstr from comment #10)
> (In reply to pg_tips from comment #4)
> > Or downgrading using the archive repos is also an option:
> > 
> > sudo dnf install fedora-repos-archive
> > sudo dnf config-manager setopt updates-archive.enabled=0
> > sudo dnf downgrade qt6-qtwayland-6.9.1-1.fc42 --enablerepo updates-archive
> 
> 1. TEMPORARY SOLUTION
> 
> Downgrading using the archive repos fixed the issue for me as well:
> 
> sudo dnf install fedora-repos-archive
> sudo dnf config-manager setopt updates-archive.enabled=0
> sudo dnf downgrade qt6-qtwayland-6.9.1-1.fc42 --enablerepo updates-archive
> 
> Thank you @pg_tips !
> 
> 2. ANNOYING SOLUTION
> 
> Also can confirm that the CTRL+ALT+F3 worked, the error instruction message
> said F1 but that one didn't work for me. This worked to get back to my
> desktop:
> 
> CTRL+ALT+F3
> loginctl unlock-session 2
> CTRL+D
> CTRL+ALT+F2
> 
> 3. MY SYSTEM INFO
> 
> Operating System: Fedora Linux 42
> KDE Plasma Version: 6.4.1
> KDE Frameworks Version: 6.15.0
> Qt Version: 6.9.1
> Kernel Version: 6.15.3-200.fc42.x86_64 (64-bit)

If you want to prevent future automatic updates of qt6-qtwayland, you can run:

sudo dnf versionlock add qt6-qtwayland

And to later remove the lock:

sudo dnf versionlock delete qt6-qtwayland

What would stop Fedora from rolling back to -1? What was trying to get fixed with -2?
Was the changed, broken part found?
What was changed?

Setting a wallpaper (per https://bugzilla.redhat.com/show_bug.cgi?id=2375328) fixes it so no need for a downgrade.

I suspect this might be an ABI breakage caused by a patch introduced in -2: https://src.fedoraproject.org/rpms/qt6-qtwayland/blob/f42/f/qtwayland-add-pointer-warp-support.patch#_236 (a new field pointerWarp was introduced which changed the layout of the QWaylandDisplay class).

In order to fix the issue, the patch in question should either be reworked to preserve ABI compatibility or removed entirely.

Rebuilding `layer-shell-qt` from source caused the issue to stop reproducing, confirming suspicions of ABI breakage.

(In reply to e.ohlms from comment #13)
> Setting a wallpaper (per
> https://bugzilla.redhat.com/show_bug.cgi?id=2375328) fixes it so no need for
> a downgrade.

That didn't fix it for me. Interestingly, it did seem to mitigate it for a few minutes - I was able to lock and unlock normally once or twice - but the issue quickly recurred.

Only by downgrading was I able to eliminate the issue on my system.

(In reply to Myrrh Periwinkle from comment #14)
> I suspect this might be an ABI breakage caused by a patch introduced in -2:
> https://src.fedoraproject.org/rpms/qt6-qtwayland/blob/f42/f/qtwayland-add-
> pointer-warp-support.patch#_236 (a new field pointerWarp was introduced
> which changed the layout of the QWaylandDisplay class).
> 
> In order to fix the issue, the patch in question should either be reworked
> to preserve ABI compatibility or removed entirely.
> 
> Rebuilding `layer-shell-qt` from source caused the issue to stop
> reproducing, confirming suspicions of ABI breakage.

Jan, what should we do here? We can try adjusting the patch or we can rebuild layer-shell-qt instead...

A related bug https://bugzilla.redhat.com/show_bug.cgi?id=2375438 appears to have been raised against layer-shell-qt. I don't have access to it, but I guess Red Hat folks may.

FEDORA-2025-6842ac8bfa (qt6-qtwayland-6.9.1-3.fc42) has been submitted as an update to Fedora 42.
https://bodhi.fedoraproject.org/updates/FEDORA-2025-6842ac8bfa

(In reply to Fedora Update System from comment #18)
> FEDORA-2025-6842ac8bfa (qt6-qtwayland-6.9.1-3.fc42) has been submitted as an
> update to Fedora 42.
> https://bodhi.fedoraproject.org/updates/FEDORA-2025-6842ac8bfa

I tested this upgrade and it really fixed the bug for me, excellent!

Operating System: Fedora Linux 42
KDE Plasma Version: 6.4.1
KDE Frameworks Version: 6.15.0
Qt Version: 6.9.1
Kernel Version: 6.15.4-200.fc42.x86_64 (64-bit)
Graphics Platform: Wayland
Processors: 16 × AMD Ryzen 7 5700U with Radeon Graphics
Memory: 24 GiB of RAM (22.8 GiB usable)
Graphics Processor: AMD Radeon Graphics

qt6-qtwayland-6.9.1-3.fc42

(In reply to Geraldo Simião from comment #19)
> (In reply to Fedora Update System from comment #18)
> > FEDORA-2025-6842ac8bfa (qt6-qtwayland-6.9.1-3.fc42) has been submitted as an
> > update to Fedora 42.
> > https://bodhi.fedoraproject.org/updates/FEDORA-2025-6842ac8bfa
> 
> I tested this upgrade and it really fixed the bug for me, excellent!
> 
> Operating System: Fedora Linux 42
> KDE Plasma Version: 6.4.1
> KDE Frameworks Version: 6.15.0
> Qt Version: 6.9.1
> Kernel Version: 6.15.4-200.fc42.x86_64 (64-bit)
> Graphics Platform: Wayland
> Processors: 16 × AMD Ryzen 7 5700U with Radeon Graphics
> Memory: 24 GiB of RAM (22.8 GiB usable)
> Graphics Processor: AMD Radeon Graphics
> 
> qt6-qtwayland-6.9.1-3.fc42

https://kojipkgs.fedoraproject.org//packages/qt6-qtwayland/6.9.1/3.fc42/x86_64/qt6-qtwayland-6.9.1-3.fc42.x86_64.rpm worked for me as well.

Saw a newer release (qt6-qtwayland-6.9.1-3.fc43) here, but haven't tested it yet:

https://koji.fedoraproject.org/koji/packageinfo?packageID=33069

Is this the same bug as bug 2375429?

(In reply to Vedran Miletić from comment #21)
> Is this the same bug as bug 2375429?

I would bet yes, based on the details and stack trace in that bug.

*** Bug 2375429 has been marked as a duplicate of this bug. ***

*** Bug 2375596 has been marked as a duplicate of this bug. ***

*** Bug 2375640 has been marked as a duplicate of this bug. ***

*** Bug 2375707 has been marked as a duplicate of this bug. ***

Hi, just in case you wanted to push the update with the revert to stable, since I have pushed another rebuilt adopting to the ABI change for fcitx5-qt, I might want another rebuilt to be pushed altogether to avoid things like https://bugzilla.redhat.com/show_bug.cgi?id=2375518 hapen again.

Thanks!

Update from Fedora KDE 41 to Fedora KDE 42, locked my screen and got the error screen that the unlocker was broken when trying to unlock it.

This is the message that was shown in a black background and white text:

"The screen locker is broken and unlocking is not possible anymore. In order to unlock it, switch to a virtual terminal (e.g. Crtl+Alt+F1), log in to your account and execute the command:

loginctrl unlock-session 2

Then log out of the virtual session by pressing Ctrl+D, and switch back to the running session (Ctrl+Alt+F2). Should you have forgotten the instructions, you can get back to this screen by pressing Ctrl+Alf+F2"

Doing that works (in my case was tty 3 Ctrl+Alt+F3).


This is the result of a kscreenlocker_greet --testing:

zazel_xes@fedora:~$ /usr/libexec/kscreenlocker_greet --testing
Locked at 1751480320
qml: The backend got an unknown wallpaper provider type. The wallpaper will now fall back to the default. Please check your wallpaper configuration!
org.kde.plasma.libtaskmanager: The PlasmaWindowManagement protocol hasn't activated in time. The client possibly got denied by kwin? Check kwin output.
file:///usr/share/plasma/shells/org.kde.plasma.desktop/contents/lockscreen/LockOsd.qml:10:1: "../osd": no such directory
Segmentation fault (core dumped)

My current wallpaper type is: Picture of the Day by Flicker

I did the following testing:

1. Change from Picture of the day to Image option: Issue persist
2. Change from Picture of the day to Plain color option: Issue persist
3. Change from Picture of the day to Slide show option: Issue persist

I stopped trying with different options, didn't see the point on going into the rest of the options.

This are my current qt6-qtwayland

azazel_xes@fedora:~$ sudo dnf list | grep "qt6-qtwayland*"
Updating and loading repositories:
Repositories loaded.
qt6-qtwayland.x86_64                                                                     6.9.1-2.fc42                                                                    updates
qt6-qtwayland.i686                                                                       6.9.1-2.fc42                                                                    updates
qt6-qtwayland-devel.i686                                                                 6.9.1-2.fc42                                                                    updates
qt6-qtwayland-devel.x86_64                                                               6.9.1-2.fc42                                                                    updates
qt6-qtwayland-examples.x86_64                                                            6.9.1-2.fc42                                                                    updates

UPDATE:

Installing https://kojipkgs.fedoraproject.org//packages/qt6-qtwayland/6.9.1/3.fc42/x86_64/qt6-qtwayland-6.9.1-3.fc42.x86_64.rpm did solved the issue.

(In reply to azazel xes from comment #29)
> UPDATE:
> 
> Installing
> https://kojipkgs.fedoraproject.org//packages/qt6-qtwayland/6.9.1/3.fc42/
> x86_64/qt6-qtwayland-6.9.1-3.fc42.x86_64.rpm did solved the issue.

After updating,KDE Plasma Desktop and Kate crash many times.See details https://bugzilla.redhat.com/show_bug.cgi?id=2376024

I ran `/usr/libexec/kscreenlocker_greet --testing`, per https://discuss.kde.org/t/how-to-screenshot-kscreenlocker/36494/10?u=rokejulianlockhart.


reporter:       libreport-2.17.15
type:           CCpp
reason:         kscreenlocker_greet killed by SIGSEGV
journald_cursor: s=a2d6d580caa24cf3a9483be7f85033e4;i=ebe3c;b=46e4489495e2471eb1b6c3cbd2603d6f;m=3906f442e;t=6390a447bca89;x=8a3d4e0987faa053
executable:     /usr/libexec/kscreenlocker_greet
cmdline:        /usr/libexec/kscreenlocker_greet --testing
cgroup:         0::/user.slice/user-1000.slice/user/app.slice/app-dev.warp.WarpPreview
rootdir:        /
uid:            1000
kernel:         6.15.4-200.fc42.x86_64
package:        kscreenlocker-6.4.1-1.fc42
runlevel:       N 5
backtrace_rating: 4
crash_function: QtWayland::wl_seat::object
comment:        I ran `/usr/libexec/kscreenlocker_greet --testing`, per https://discuss.kde.org/t/how-to-screenshot-kscreenlocker/36494/10?u=rokejulianlockhart.

Usually, it works. However, if I attempt to capture it with Spectacle, if I lock at the exact moment that Spectacle attempts to capture it, it crashes.


reporter:       libreport-2.17.15
type:           CCpp
reason:         kscreenlocker_greet killed by SIGSEGV
journald_cursor: s=c1f108f1ef4e48808a377c0a73f168fc;i=7f2eac;b=b2a134807274490680ec642ce3d82658;m=172d72b33;t=6390cdf244f07;x=5de657c8fa41983d
executable:     /usr/libexec/kscreenlocker_greet
cmdline:        /usr/libexec/kscreenlocker_greet --testing
cgroup:         0::/user.slice/user-1000.slice/user/app.slice/app-dev.warp.WarpPreview
rootdir:        /
uid:            1000
kernel:         6.15.4-200.fc42.x86_64
package:        kscreenlocker-6.4.1-1.fc42
runlevel:       N 5
backtrace_rating: 4
crash_function: QtWayland::wl_seat::object
comment:        Usually, it works. However, if I attempt to capture it with Spectacle, if I lock at the exact moment that Spectacle attempts to capture it, it crashes.

FEDORA-2025-6842ac8bfa (qt6-qtwayland-6.9.1-3.fc42) has been pushed to the Fedora 42 stable repository.
If problem still persists, please make note of it in this bug report.

The needinfo request[s] on this closed bug have been removed as they have been unresolved for 120 days