Sisyphus
2306ac2236
Critical fixes from Linux kernel cross-reference:
- execlists.rs flush_pending(): write upper 32 bits FIRST, then lower.
BSpec requires upper-first on legacy ELSP; GPU latches on lower write.
Previously wrote lower then upper — stale upper dword used by GPU.
- execlists.rs init(): write only INHIBIT_SYN_CTX_SWITCH to RING_CONTEXT_CONTROL.
Linux init_common_regs() disables ENGINE_CTX_RESTORE_INHIBIT and
RS_CTX_ENABLE for normal operation. Our old code set restore inhibit,
preventing context save/restore on context switch — GPU would hang.
- context.rs: LRC image offsets were MMIO register offsets (0x30, 0x34, 0x38).
LRC state layout is different — CTX_CONTEXT_CONTROL is dword index 3 (byte 12).
Fixed to match Linux intel_lrc_reg.h dword layout:
LRC_CTX_CTRL_OFFSET = 12 (was 0x02)
LRC_HEAD_OFFSET = 20 (was 0x30)
LRC_TAIL_OFFSET = 28 (was 0x34)
LRC_RING_START_OFFSET = 36 (was 0x38)
Added LRC_RING_CTL_OFFSET = 40
- context.rs: corrected CTX_CTRL_INHIBIT_SYN_CTX_SWITCH from bit 2 to bit 3
to match Linux RING_CONTEXT_CONTROL bit layout at 0x244.
- ring.rs: added gpu_address() method to expose ring GGTT address for
LRC descriptor construction.
- mod.rs: wire execlist submission path after ring batch submit in
hw_submit_to_ring(), creating LRC descriptor and submitting via ExeclistPort.
- display.rs: program HDMI infoframes (AVI, audio, VSIF) on port enable.
Red Bear OS
A microkernel operating system written in Rust, derived from Redox OS
What is Red Bear OS?
Red Bear OS is a general-purpose, Unix-like operating system with a microkernel architecture, written in Rust. It is a full fork of Redox OS, frozen at release 0.1.0, with added hardware support, filesystem drivers, and a KDE Plasma desktop path.
Goals:
- AMD & Intel parity — first-class support for both platforms on bare metal
- KDE Plasma desktop — Wayland-based desktop environment via the KWin compositor
- Hardware GPU acceleration — AMD GPU (amdgpu) and Intel GPU drivers via
redox-drm - Modern subsystems — USB, Wi‑Fi, Bluetooth, ext4, GRUB, D-Bus
- Offline-first builds — reproducible from archived, BLAKE3-verified sources
Quick Start
Prerequisites
Linux x86_64 host with Rust nightly, QEMU, nasm, and standard build tools.
See the Redox Build Guide for full setup.
Build & Run
# Clone
git clone https://gitea.redbearos.org/vasilito/RedBear-OS.git
cd RedBear-OS
# Build and run the desktop target in QEMU
./scripts/run.sh --build
# Build a live ISO for bare metal
./scripts/build-iso.sh redbear-full
# Build the text-only recovery target
./scripts/run.sh --build --config redbear-mini
Repository Hosting
The canonical Red Bear OS Git server is Gitea at
https://gitea.redbearos.org/vasilito/RedBear-OS.git. GitHub is not a Red Bear OS source of
truth and must not be used for pushes, issues, releases, or project coordination.
Public Scripts
| Script | Purpose |
|---|---|
scripts/run.sh |
Build and run in QEMU (-b to build, -c <config> for target) |
scripts/build-iso.sh |
Build a live ISO for bare-metal boot |
scripts/build-all-isos.sh |
Build all live ISO targets |
scripts/network-boot.sh |
PXE network boot helper |
scripts/dual-boot.sh |
Dual-boot installation helper |
Config Targets
| Target | Type | Description |
|---|---|---|
redbear-full |
Desktop | Wayland + KDE + GPU drivers + D-Bus services |
redbear-mini |
Console | Text-only recovery / install target |
redbear-grub |
Console | Text-only with GRUB boot manager |
Current Status
Red Bear OS boots to a login prompt in QEMU with working wired networking, D-Bus system bus, hardware detection daemons, and filesystem support (RedoxFS, ext4, FAT).
| Area | Status |
|---|---|
| Boot (ACPI/x2APIC/SMP) | ✅ Bare-metal proven |
| Userspace drivers (PCI, storage, net) | ✅ Working in QEMU |
| D-Bus system bus + services | ✅ Working (login1, PolicyKit, UDisks, UPower) |
| ext4 / FAT filesystems | ✅ Compiles, installer-wired |
| POSIX gaps (relibc) | 🚧 Bounded Wayland-facing support |
| DRM/KMS display drivers | 🚧 AMD + Intel compile; HW validation pending |
| Wayland compositor | 🚧 Bounded proof; Qt6/KF6 clients crash at init |
| KDE Plasma desktop | 🔄 In progress (Qt6/KF6 compile; KWin/QML blocked) |
| Wi‑Fi / Bluetooth | 📋 Planned (architected, implementation pending) |
How It Works
Red Bear OS uses a userspace driver model — all drivers run as unprivileged daemons:
Kernel (microkernel)
└── schemes: memory, irq, event, pipe, debug
└── Driver daemons (userspace)
├── pcid → PCI enumeration
├── e1000d → Intel ethernet
├── xhcid → USB controller
└── vesad → Display framebuffer
The kernel provides minimal services (memory, interrupts, IPC). Everything else — filesystems, networking, graphics, input — runs in userspace.
Documentation
- Implementation Plan — roadmap and execution model
- Desktop Path Plan — kernel → DRM → Mesa → Wayland → KDE
- D-Bus Integration — session bus architecture
- USB Plan — USB stack design
- Wi‑Fi Plan — wireless architecture
- Bluetooth Plan — BT stack design
- Documentation Index — full doc map
Contributing
Red Bear OS uses a full fork model. Upstream Redox sources are frozen and archived. All custom work lives in local/:
local/
├── sources/ # Red Bear source forks (git repos, directly editable)
├── recipes/ # Custom packages (drivers, GPU, system)
├── docs/ # Integration and planning docs
└── scripts/ # Build, test, and release tooling
We welcome contributions made with or without AI assistance — we care about quality, not how the code was produced.
License
MIT — same as upstream Redox OS.