https://bugs.kde.org/show_bug.cgi?id=507488
Bug ID: 507488
Summary: Folder thumbnails fail to generate on bcachefs file
system
Classification: Frameworks and Libraries
Product: frameworks-kio
Version First 6.16.0
Reported In:
Platform: Arch Linux
OS: Linux
Status: REPORTED
Severity: minor
Priority: NOR
Component: general
Assignee: [email protected]
Reporter: [email protected]
CC: [email protected]
Target Milestone: ---
Created attachment 183513
--> https://bugs.kde.org/attachment.cgi?id=183513&action=edit
Folder with and without a thumbnail
SUMMARY
If a folder is situated on a bcachefs partition its icon in Dolphin will not
display thumbnails of its contents regardless of the preview options.
STEPS TO REPRODUCE
1. Setup the environment.
> $ touch fs && truncate fs --size 128M && mkfs.bcachefs fs && sudo mount fs
> /mnt && sudo chown $USER:$USER /mnt && mkdir /mnt/folder && cp
> /usr/share/plasma/avatars/photos/Dog.png /mnt/folder/picture.png
2. Open the Dolphin file manager.
3. Enable previews for folders and pictures.
4. Open the `/mnt` directory.
Alternatively
2. Compile KIO with `cmake -DBUILD_TESTING=ON ...`
3. Run `build/bin/previewtest`
4. Select `/mnt/folder` and press `Generate`
OBSERVED RESULT
Icon of `/mnt/folder` keeps its stock appearance.
`build/bin/previewtest` displays `failed`.
EXPECTED RESULT
Folder `/mnt/folder` has on overlaid thumbnail of `/mnt/folder/picture.png` on
its icon.
`build/bin/previewtest` displays an icon.
SOFTWARE/OS VERSIONS
Operating System: Arch Linux
KDE Plasma Version: 6.4.3
KDE Frameworks Version: 6.16.0
Qt Version: 6.9.1
Kernel Version: 6.15.7-zen1-1-zen (64-bit)
Graphics Platform: Wayland
Processors: 12 × AMD Ryzen 5 5600G with Radeon Graphics
Memory: 32 GiB of RAM (27.3 GiB usable)
Graphics Processor: AMD Radeon Graphics
ADDITIONAL INFORMATION
The cause of this bug is a file size check at
https://invent.kde.org/frameworks/kio/-/blob/v6.16.0/src/gui/previewjob.cpp?ref_type=tags#L580
> const KIO::filesize_t size =
> static_cast<KIO::filesize_t>(statResult.numberValue(KIO::UDSEntry::UDS_SIZE,
> 0));
> if (size == 0) {
> qCDebug(KIO_GUI) << "PreviewJob: skipping an empty file, migth be a
> broken symlink" << d->currentItem.item.url();
> d->determineNextFile();
> return;
> }
It seems on bcachefs stat'ing any folder results in the reported size always
being 0.
> $ stat /mnt/folder
> File: /mnt/folder
> Size: 0 Blocks: 0 IO Block: 4096 directory
> Device: 253,0 Inode: 74608 Links: 2
> Access: (0755/drwxr-xr-x) Uid: ( 1000/ user) Gid: ( 1000/ group)
> Access: 2025-07-25 XX:XX:XX.XXXXXXXXX -XXXX
> Modify: 2025-07-25 XX:XX:XX.XXXXXXXXX +XXXX
> Change: 2025-07-25 XX:XX:XX.XXXXXXXXX -XXXX
> Birth: 2025-07-25 XX:XX:XX.XXXXXXXXX +XXXX
Commenting out the above size check restores the folder thumbnails.
I have also checked and the bug is still present on the master branch
(f60be14b9ed1b90273d1ef9e2ed145afdd3db6e9) in file
https://invent.kde.org/frameworks/kio/-/blob/master/src/gui/filepreviewjob.cpp#L160
--
You are receiving this mail because:
You are watching all bug changes.
