Bug 504913

SUMMARY

On FreeBSD 14.2 using Plasma 6 and Qt6, the kioworker process crashes when generating image thumbnails in Dolphin if the Oxygen style is enabled. Switching to another style (e.g. Breeze) resolves the issue.

Environment:

    OS: FreeBSD 14.2-RELEASE
    KDE Plasma: 6.3.5 (installed via pkg)
    Qt: 6.8.3
    plasma6-oxygen 6.3.5
    Theme: oxygen6-style
    Dolphin: installed via pkg, Plasma 6 version
    Display Server: X11
    Installed via: FreeBSD binary packages (pkg)

Steps to Reproduce:

1. Set Oxygen as the global theme.
2. Launch dolphin in a directory with image files.
3. Observe that new image thumbnails are not generated.

Notice that, in case Dolphin is launched from a terminal, kioworker.core files appear in the working directory. If I use gdb to inspect the core dump I see kioworker crashes in liboxygenstyle6 via a call to xcb_intern_atom().

Backtrace (from gdb):

#0  xcb_send_request_with_fds64 () from /usr/local/lib/libxcb.so.1
#1  xcb_intern_atom () from /usr/local/lib/libxcb.so.1
#2  Oxygen::Helper::createAtom(QString const&) const () from /usr/local/lib/liboxygenstyle6.so.6
#3–#6 oxygen6.so
#7  QStyleFactory::create(QString const&) from libQt6Widgets.so.6
#8  QApplication::style()
#9  QApplicationPrivate::initialize()
#10 QApplicationPrivate::init()
#11 kdemain() from thumbnail.so

Notes:
Using another style like Breeze resolves the issue permanently.



Full gdb output:

$ gdb /usr/local/lib/libexec/kf6/kioworker --core=kioworker.core 
GNU gdb (GDB) 15.1 [GDB v15.1 for FreeBSD]
Copyright (C) 2024 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-portbld-freebsd14.2".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
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Reading symbols from /usr/local/lib/libexec/kf6/kioworker...
(No debugging symbols found in /usr/local/lib/libexec/kf6/kioworker)
[New LWP 110755]
[New LWP 110836]
[New LWP 110850]
[New LWP 110851]
[New LWP 110852]
[New LWP 110853]
[New LWP 110854]
[New LWP 110855]
[New LWP 110859]
[New LWP 110860]
[New LWP 110861]
Core was generated by `/usr/local/lib/libexec/kf6/kioworker /usr/local/lib/qt6/plugins/kf6/kio/thumbnai'.
Program terminated with signal SIGSEGV, Segmentation fault.
Address not mapped to object.
#0  0x0000000842846823 in xcb_send_request_with_fds64 () from /usr/local/lib/libxcb.so.1
[Current thread is 1 (LWP 110755)]
(gdb) bt
#0  0x0000000842846823 in xcb_send_request_with_fds64 () from /usr/local/lib/libxcb.so.1
#1  0x000000084284e9df in xcb_intern_atom () from /usr/local/lib/libxcb.so.1
#2  0x0000000890268b75 in Oxygen::Helper::createAtom(QString const&) const () from /usr/local/lib/liboxygenstyle6.so.6
#3  0x000000088b7b6b7d in ?? () from /usr/local/lib/qt6/plugins/styles/oxygen6.so
#4  0x000000088b7b6ace in ?? () from /usr/local/lib/qt6/plugins/styles/oxygen6.so
#5  0x000000088b793cd5 in ?? () from /usr/local/lib/qt6/plugins/styles/oxygen6.so
#6  0x000000088b7c38e9 in ?? () from /usr/local/lib/qt6/plugins/styles/oxygen6.so
#7  0x000000084e1a29f2 in QStyleFactory::create(QString const&) () from /usr/local/lib/qt6/libQt6Widgets.so.6
#8  0x000000084e0fe9e3 in QApplication::style() () from /usr/local/lib/qt6/libQt6Widgets.so.6
#9  0x000000084e0fe3c9 in QApplicationPrivate::initialize() () from /usr/local/lib/qt6/libQt6Widgets.so.6
#10 0x000000084e0fd91c in QApplicationPrivate::init() () from /usr/local/lib/qt6/libQt6Widgets.so.6
#11 0x0000000847422d5f in kdemain () from /usr/local/lib/qt6/plugins/kf6/kio/thumbnail.so
#12 0x000000000020243e in ?? ()
#13 0x0000000828462c3a in __libc_start1 () from /lib/libc.so.7
#14 0x0000000000202110 in ?? ()

Kind regards
Paolo