Bug 487860

Summary:	Nested kwin_wayland 6.0.90.1's window didn't appear in VMs using the llvmpipe driver
Product:	[Plasma] kwin	Reporter:	Matt Fagnani <matt.fagnani>
Component:	wayland-generic	Assignee:	KWin default assignee <kwin-bugs-null>
Status:	CONFIRMED ---
Severity:	normal	CC:	kde
Priority:	NOR	Keywords:	qt6
Version First Reported In:	git-stable-Plasma/6.1
Target Milestone:	---
Platform:	Fedora RPMs
OS:	Linux
See Also:	https://bugs.kde.org/show_bug.cgi?id=487857 https://bugs.kde.org/show_bug.cgi?id=487217
Latest Commit:		Version Fixed/Implemented In:
Sentry Crash Report:

Description Matt Fagnani 2024-05-31 22:22:25 UTC

SUMMARY

I booted the Fedora Rawhide/41 KDE Plasma live image Fedora-KDE-Live-x86_64-Rawhide-20240531.n.0.iso in a QEMU/KVM VM using GNOME Boxes with 3D acceleration disabled using the llvmpipe driver from mesa 24.1.0. Plasma 6.0.90 on Wayland started. I started Konsole. I tried to run a nested kwin_wayland session using the instructions at https://community.kde.org/KWin/Wayland
export $(dbus-launch)
kwin_wayland --xwayland 

The nested kwin_wayland window didn't appear, but it didn't crash. Just a task manager Wayland icon labelled KDE Wayland compositor WL-0 was shown which didn't show the window when I tried to click on it or maximize it. The following output was in Konsole which showed KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied errors among others including kwin_wayland_backend: Could not find a suitable render format.

export $(dbus-launch)
kwin_wayland --xwayland 
No backend specified, automatically choosing Wayland because WAYLAND_DISPLAY is set
unable to lock lockfile /run/user/1000/wayland-0.lock, maybe another compositor is running
Accepting client connections on sockets: QList("wayland-1")
OpenGL vendor string:                   Mesa
OpenGL renderer string:                 llvmpipe (LLVM 18.1.6, 256 bits)
OpenGL version string:                  4.5 (Core Profile) Mesa 24.1.0
OpenGL shading language version string: 4.50
Driver:                                 LLVMpipe
GPU class:                              Unknown
OpenGL version:                         4.5
GLSL version:                           4.50
Mesa version:                           24.1
Requires strict binding:                no
Virtual Machine:                        no
OpenGL vendor string:                   Mesa
OpenGL renderer string:                 llvmpipe (LLVM 18.1.6, 256 bits)
OpenGL version string:                  4.5 (Core Profile) Mesa 24.1.0
OpenGL shading language version string: 4.50
Driver:                                 LLVMpipe
GPU class:                              Unknown
OpenGL version:                         4.5
GLSL version:                           4.50
Mesa version:                           24.1
Requires strict binding:                no
Virtual Machine:                        no
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
kwin_wayland_backend: Could not find a suitable render format
libEGL warning: egl: failed to create dri2 screen
Refusing to try glamor on llvmpipe
EGL setup failed, disabling glamor
Failed to initialize glamor, falling back to sw
The XKEYBOARD keymap compiler (xkbcomp) reports:
> Warning:          Unsupported maximum keycode 708, clipping.
>                   X11 cannot support keycodes above 255.
> Warning:          Could not resolve keysym XF86KbdInputAssistPrevgrou
> Warning:          Could not resolve keysym XF86KbdInputAssistNextgrou
Errors from xkbcomp are not fatal to the X server
MESA: error: ZINK: failed to choose pdev
libEGL warning: egl: failed to create dri2 screen
QSoundEffect(pulseaudio): Error decoding source file:///usr/share/maliit/keyboard2/sounds/key_tick2_quiet.wav
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied
KMS: DRM_IOCTL_MODE_CREATE_DUMB failed: Permission denied

This problem happened 3/3 times.

STEPS TO REPRODUCE
1. Boot a Fedora 40 KDE Plasma installation updated to 2024-5-31 with updates-testing enabled
2. Log in to Plasma 6.0.5 on Wayland
3. Start Konsole
4. Install GNOME Boxes if it isn't already with sudo dnf install gnome-boxes
5. Download Fedora-KDE-Live-x86_64-Rawhide-20240531.n.0.iso from https://koji.fedoraproject.org/koji/buildinfo?buildID=2459206
6. Start GNOME Boxes
7. Boot Fedora-KDE-Live-x86_64-Rawhide-20240531.n.0.iso in a GNOME Boxes QEMU/KVM VM with 3 GiB RAM, UEFI enabled, and 3D acceleration disabled using the llvmpipe mesa driver
8. Start Konsole
9. In Konsole, run 
export $(dbus-launch)
kwin_wayland --xwayland 

OBSERVED RESULT
Nested kwin_wayland 6.0.90.1's window didn't appear in VMs using the llvmpipe driver

EXPECTED RESULT
Nested kwin_wayland 6.0.90.1's window should have appeared

SOFTWARE/OS VERSIONS
Linux/KDE Plasma: Fedora Rawhide
(available in About System)
KDE Plasma Version: 6.0.90
KDE Frameworks Version: 6.2.0
Qt Version: 6.7.1

ADDITIONAL INFORMATION

Nested kwin_wayland 6.0.5 and 6.0.4 crashed with different traces from each other in VMs using llvmpipe https://bugs.kde.org/show_bug.cgi?id=487857 https://bugs.kde.org/show_bug.cgi?id=487217