Files
RedBear-OS/local/recipes/kde/kwin
vasilito 10caab7085 boot: real Wayland compositor, Intel DRM Gen8-Gen12, kernel 4GB fix, virtio-gpu driver
Comprehensive boot process improvement across the entire stack:

Compositor (NEW): Real Rust Wayland display server (690 lines)
- Full XDG shell protocol (15/15 protocols implemented and verified)
- wl_shm.format, xdg_wm_base, xdg_surface.get_toplevel support
- wl_buffer.release lifecycle, buffer composite to framebuffer
- Framebuffer mapping via scheme:memory (Redox) with fallback
- PID/status files for greeterd health checks
- Integration test suite (3 cases passing)
- Diagnostic tool: redbear-compositor-check

DRM/KMS Chain:
- KWIN_DRM_DEVICES=/scheme/drm/card0 wired through init→greeterd→compositor
- session-launch propagates KWIN_DRM_DEVICES (new test, 11/11 pass)
- DRM auto-detect + 5s wait loop in compositor wrapper
- Boot verified: compositor uses DRM backend in QEMU

Intel DRM:
- Gen8-Gen12 supported with firmware (SKL/KBL/CNL/ICL/GLK/RKL/DG1/TGL/ADLP/DG2/MTL/ARL/LNL/BMG)
- Gen4-Gen7 device IDs recognized, unsupported with clear error message
- Linux 7.0 i915 reference for all 200+ device IDs
- Display fixes: sticky pipe refresh, PIPE=4/PORT=6, 64-bit page flip, EDID skeleton
- 4 durability patches wired into recipe

VirtIO GPU Driver (NEW):
- 220-line DRM/KMS backend for QEMU virtio-gpu
- Full GpuDriver trait implementation (11 methods)
- PCI BAR0 framebuffer mapping, connector/mode info, GEM management

Kernel:
- 4GB RAM hang root cause: MEMORY_MAP overflow at 512 entries → fixed to 1024
- Canary chain R S 1 2 3 4 5 6 7 (9 COM1 checkpoints through boot)
- Verified: kernel boots at 4GB with all canaries present
- 3 durability patches (P0-canary, P1-memory-overflow)

Live ISO:
- Preload capped at 1 GiB with partial preload messaging
- P5 patch wired into bootloader recipe

Greeter:
- Startup progress logging (4 checkpoints)
- QML crash diagnostic (exit code 1 → specific error message)
- greeterd tests: 8/8 pass

Boot Daemons:
- dhcpd: auto-detect interface from /scheme/netcfg/ifaces/
- i2c-gpio-expanderd: I2C decode retry (3× with 50ms delay)
- ucsid: same I2C decode hardening
- Compositor: safe framebuffer fallback (prevents crash)

Qt6 Toolchain:
- -march=x86-64 for CPU compatibility (prevents invalid_opcode on core2duo)
- -fpermissive for header compatibility (unlinkat/linkat redefinition)

Documentation:
- BOOT-PROCESS-IMPROVEMENT-PLAN.md (comprehensive, 320 lines)
- PROFILE-MATRIX.md: ISO organization, RAM requirements, known issues
- BOOT-PROCESS-ASSESSMENT.md: Phase 7 kernel hang diagnosis
- Deleted 4 stale docs (BAREMETAL-LOG, ACPI-FIXES, 02-GAP-ANALYSIS, _CUB_RBPKGBUILD)
- Cross-references updated across all docs

KWin stubs replaced with real compositor delegation.
redbear-kde-session script created for post-login session launch.
30+ files, 10 patches, 3 binaries, 22 tests, 0 errors.
2026-04-28 06:18:37 +01:00
..

KWin

KWin is an easy to use, but flexible, composited Window Manager for Xorg windowing systems (Wayland, X11) on Linux. Its primary usage is in conjunction with a Desktop Shell (e.g. KDE Plasma Desktop). KWin is designed to go out of the way; users should not notice that they use a window manager at all. Nevertheless KWin provides a steep learning curve for advanced features, which are available, if they do not conflict with the primary mission. KWin does not have a dedicated targeted user group, but follows the targeted user group of the Desktop Shell using KWin as it's window manager.

KWin is not...

  • a standalone window manager (c.f. openbox, i3) and does not provide any functionality belonging to a Desktop Shell.
  • a replacement for window managers designed for use with a specific Desktop Shell (e.g. GNOME Shell)
  • a minimalistic window manager
  • designed for use without compositing or for X11 network transparency, though both are possible.

Contributing to KWin

Please refer to the contributing document for everything you need to know to get started contributing to KWin.

Contacting KWin development team

Support

Application Developer

If you are an application developer having questions regarding windowing systems (either X11 or Wayland) please do not hesitate to contact us. Preferable through our mailing list. Ideally subscribe to the mailing list, so that your mail doesn't get stuck in the moderation queue.

End user

Please contact the support channels of your Linux distribution for user support. The KWin development team does not provide end user support.

Reporting bugs

Please use KDE's bugtracker and report for product KWin.

Guidelines for new features

A new Feature can only be added to KWin if:

  • it does not violate the primary missions as stated at the start of this document
  • it does not introduce instabilities
  • it is maintained, that is bugs are fixed in a timely manner (second next minor release) if it is not a corner case.
  • it works together with all existing features
  • it supports both single and multi screen (xrandr)
  • it adds a significant advantage
  • it is feature complete, that is supports at least all useful features from competitive implementations
  • it is not a special case for a small user group
  • it does not increase code complexity significantly
  • it does not affect KWin's license (GPLv2+)

All new added features are under probation, that is if any of the non-functional requirements as listed above do not hold true in the next two feature releases, the added feature will be removed again.

The same non functional requirements hold true for any kind of plugins (effects, scripts, etc.). It is suggested to use scripted plugins and distribute them separately.