RedBear-OS/local/docs/CONSOLE-TO-KDE-DESKTOP-PLAN.md

Red Bear OS: Console to Hardware-Accelerated KDE Desktop on Wayland

Version: 3.0 (2026-04-29) Replaces: v2.2 and all prior desktop-path documents Status: Canonical desktop path plan — OLW-drafted, build-verified Implementation status (2026-04-30): VERIFIED scope is the currently buildable KDE surface on redbear-full; packages still blocked by Qt6Quick/QML downstream proof, Qt6::Sensors/libinput, empty-package output, or direct recipe failure stay commented out in config and are not part of this verification claim.

Purpose

This is the single authoritative plan for the Red Bear OS path from console boot to a hardware-accelerated KDE Plasma desktop running on Wayland. It is rewritten in v3.0 based on a full end-to-end reassessment of every component in the chain: DRM/KMS → Mesa → Wayland Compositor → Input/Seat → Greeter/Login → KDE Plasma.

This plan answers: what is the current state of every layer, what are the honest blockers, and what must happen, in what order, to reach a usable KDE Plasma desktop.

Full Chain Assessment (2026-04-29)

LAYER 1 — DRM/KMS

Component	Status	Config	Notes
redox-drm	builds	enabled	Intel Gen8-Gen12 + AMD device support + quirk tables; MSI-X/legacy IRQ fallback; no hardware validation
libdrm	builds	enabled	Provides libdrm_amdgpu; amdgpu device support
firmware-loader	builds	enabled	scheme:firmware; blob loading verified
GPU firmware	fetched	partial	amdgpu/i915 blobs available via fetch-firmware.sh
virtio-gpu	builds	in redox-drm	220-line DRM/KMS backend for QEMU testing
CS ioctl	protocol exists	redox-drm scheme	Private CS submit/wait ioctls defined; hardware backend returns unavailable (GPU driver gate)

Verdict: Display infrastructure exists. Hardware rendering blocked on GPU driver backend + hardware validation (CS ioctl protocol exists).

LAYER 2 — Mesa/Graphics

Component	Status	Config	Notes
mesa	builds	enabled	llvmpipe software renderer; EGL=on, GBM=on, GLES2=on, platform=redox
radeonsi (AMD HW)	not built	—	Not cross-compiled for Redox target
iris (Intel HW)	not built	—	Not cross-compiled for Redox target
OSMesa	builds	enabled	Off-screen software rendering

Verdict: Software rendering works (llvmpipe). Hardware renderers need cross-compilation; CS ioctl protocol exists, backend validation deferred (hardware gate).

LAYER 3 — Wayland/Compositor

Component	Status	Config	Notes
libwayland 1.24.0	builds	enabled	Wayland protocol library; durability patch applied
wayland-protocols	builds	enabled	Protocol XML definitions
redbear-compositor	builds, 788 lines	enabled	Real Rust Wayland compositor; zero warnings; 3/3 tests; known limitations: heap-memory framebuffer, payload-byte SHM, NUL-terminated wire encoding
kwin	stub	enabled (but stub)	Stub — recipe downloads real KWin v6.3.4 source but build script only creates wrapper scripts + cmake config stubs; delegates to redbear-compositor; real cmake build requires Qt6Quick/QML downstream proof
redbear-compositor-check	builds	in redbear-compositor pkg	Verifies compositor socket, binaries, framebuffer

Verdict: Working bounded compositor proof. Real KWin gated on Qt6Quick/QML downstream proof.

LAYER 4 — Input/Seat

Component	Status	Config	Notes
evdevd	builds	enabled	scheme:evdev; 65 unit tests; event device semantics verified
libinput	builds, suppressed	config: libinput = "ignore"	Builds but suppressed in redbear-full; evdevd handles input natively for bounded proof
udev-shim	builds	enabled	scheme:udev; device enumeration; 15 unit tests
seatd/seatd-redox	builds	enabled	meson build; 13_seatd.service wired; DRM lease via redox-drm
libevdev	suppressed	commented	build needed header

Verdict: Input path works through evdevd + udev-shim. seatd wired for compositor seat access. libinput deferred (not needed for bounded proof).

LAYER 5 — Greeter/Login

Component	Status	Config	Notes
redbear-authd	builds	enabled	SHA-crypt/Argon2 auth; /etc/passwd + /etc/shadow
redbear-session-launch	builds	enabled	Session bootstrap (uid/gid/env/runtime-dir)
redbear-greeter	builds	enabled	greeterd orchestrator + Qt6/QML UI + compositor wrapper
redbear-sessiond	builds	enabled	org.freedesktop.login1 D-Bus broker (zbus)
dbus	builds	enabled	1.16.2; system bus wired; session bus partially
Greeter QEMU proof	passes	—	GREETER_HELLO=ok, GREETER_VALID=ok, GREETER_INVALID=ok
redbear-kde-session	builds	enabled	KDE session launcher (DRM/virtual backend, plasmashell/kded6)

Verdict: Greeter/login path works end-to-end in QEMU with bounded proof. KDE session launcher ready.

LAYER 6 — KDE/Plasma

Component	Status	Config	Notes
qtbase 6.11.0	builds	enabled	Core+Gui+Widgets+DBus+Wayland; 7 libs + 12 plugins
qtdeclarative	builds	enabled	Qt6Quick metadata exported; QML JIT disabled for Redox; downstream proof insufficient
qtwayland	builds	enabled	Wayland QPA plugin
qtsvg	builds	enabled	SVG support
KDE/Plasma surface (48 recipes)	37 build / 11 blocked	36 enabled in config, 12 commented/ignored. See DESKTOP-STACK-CURRENT-STATUS.md for exact breakdown.
kf6-kio	builds	enabled	HostInfo stub (direct QHostInfo::fromName replaces QtConcurrent chain) — pkgar in repo
kirigami	blocked: QML gate	ignored in config	QQuickWindow/QQmlEngine headers don't exist on Redox
kf6-knewstuff	blocked	commented out	Empty package — cmake succeeds but core source produces no libs with QtQuick off
kf6-kwallet	builds	enabled	Real API-only core wallet cmake build; QML/GPG disabled
kf6-attica	builds	enabled (NEW)	Minimal core library (v6.10.0, 2.4MB pkgar in repo)
plasma-framework	blocked (QML gate)	commented out	Depends on kirigami
plasma-workspace	blocked	commented out	Depends on kf6-knewstuff payload + kwin real build
plasma-desktop	blocked (transitive)	commented out	Depends on plasma-workspace
kdecoration	builds	transitively via plasma-workspace	Window decoration library
kf6-kwayland	builds	enabled	Qt/C++ Wayland protocol wrapper
plasma-wayland-protocols	builds	transitively	XML protocol definitions

Verdict: KDE/Plasma recipes exist (48 total). 36 build, 11 blocked with documented reasons. Real Plasma session requires resolving platform prerequisites: QML JIT for kirigami, Qt6::Sensors for kwin real build.

LAYER 7 — Validation Infrastructure

Artifact	Count	Status
Phase 1-5 check binaries	15+	Zero warnings, Redox-target verified
Test harness scripts	12	Syntax-clean, guest+QEMU modes
Oracle verification rounds	20+	Phases 1-5 all verified
Host cargo check	3 crates	Zero warnings
Redox-target build	3 crates	Successful (make r.*)
Full OS build	exists	build/x86_64/redbear-full.iso + .img available; rebuild via make all CONFIG_NAME=redbear-full

Honest Blocker Classification

Blocker	What's needed
Qt6Quick/QML downstream proof	Qt6Quick/QML runtime proof (QML JIT disabled for Redox); blocks kirigami + real KWin + Plasma
Hardware GPU validation	Real AMD/Intel GPU; blocks hardware backend validation; CS ioctl protocol exists
Bare-metal validation	Real hardware; blocks all hardware claims

Deferred (not on critical path for minimal session proof)

Item	Reason
kf6-knewstuff/kwallet	real cmake builds attempted; QML disabled; not on critical path for minimal session
libinput	evdevd handles input natively for bounded proof; libinput builds but suppressed in config
libevdev	header build needed; not blocking

Critical Path (updated)

Layer 1 (DRM) ▸ Layer 2 (Mesa sw) ▸ Layer 3 (compositor proof) ▸
Layer 4 (input/seat) ▸ Layer 5 (greeter) ✓ ▸ Layer 6 (Plasma preflight) ✓

Environmental gate (Qt6Quick): Layer 3 (KWin runtime proof) ← Qt6Quick/QML downstream proof
Environmental gate (hardware): Layer 1 (GPU CS ioctl backend) ← hardware + Mesa HW cross-compilation

Current Config Surface

config/redbear-full.toml enables the full desktop-capable surface including:

• 37 KDE packages (34 KF6 + kdecoration + kglobalacceld + kwin); 11 blocked/ignored with documented reasons
• kf6-attica (NEW — minimal core library, 2.4MB pkgar in repo)
• mesa + libdrm (GPU software stack)
• qtbase + qtdeclarative + qtwayland + qtsvg + qt6-wayland-smoke
• seatd + redbear-authd + redbear-session-launch + redbear-greeter (via redbear-mini)
• dbus + firmware-loader + redox-drm + evdevd + udev-shim
• redbear-compositor (real Rust Wayland compositor, kwin delegates to it)
• plus inherited packages from redbear-mini profile

Verification Steps (build-verified; supplementary QEMU validation) (ordered by impact)

1. Rebuild full OS image — make all CONFIG_NAME=redbear-full (harddrive.img for QEMU) or make live CONFIG_NAME=redbear-full (ISO for bare metal); existing artifacts at build/x86_64/

2. Qt6Quick/QML runtime proof — validate Qt6Quick downstream consumers with QML JIT disabled for Redox; unblocks kirigami → real KWin → full Plasma session

3. GPU CS ioctl implementation — implement command submission in redox-drm; unblocks hardware rendering path

4. Mesa HW renderer cross-compilation — build radeonsi/iris for Redox target; requires CS ioctl for validation

5. Real KWin build — validate the current real KWin build with Qt6Quick/QML downstream proof; unblocks full KDE Plasma session

6. Hardware validation — AMD + Intel bare-metal testing for all layers

Evidence Model

Evidence class	What it means
Source	Code exists in tree
Host build-verified	cargo check zero warnings on Linux
Redox build-verified	make r.* successful on x86_64-unknown-redox
Runtime-validated	Exercised in QEMU or bare metal
Hardware-validated	Exercised on real AMD/Intel hardware

Current state: Layers 1-4 are Redox build-verified (all 3 Red Bear crates cook on x86_64-unknown-redox). Layer 5 (greeter) is runtime-validated in QEMU. Layer 6 (Plasma) and hardware paths remain at build-verified preflight level.