vasilito
5e44191c90
Phase R6 (2026-06-07) extends the xHCI controller quirk layer with five
new XHCI_* bit positions from Linux 7.1's drivers/usb/host/xhci.h, three
new PCI table entries from xhci-pci.c, and an xhcid-side observability
hook for the unenforced flags. Bit positions match Linux exactly per
the existing docstring convention on XhciControllerQuirkFlags.
Five new xHCI flags (24 total, no collisions):
- XHCI_SSIC_PORT_UNUSED (bit 22) — Intel Cherryview 0x22b5
- XHCI_MISSING_CAS (bit 24) — Intel CV/SP/APL/DV
- XHCI_BROKEN_PORT_PED (bit 25) — platform-only in Linux
- XHCI_HW_LPM_DISABLE (bit 29) — platform-only in Linux
- XHCI_BROKEN_D3COLD_S2I (bit 41) — AMD Renoir 0x1639
XHCI_EP_CTX_BROKEN_DCS (bit 42) was the fifth entry on the plan's list
but is a Linux reserved-but-unused bit: only the BIT_ULL(42) definition
exists, with no consumer code anywhere and no PCI/vendor association.
Adding it would have been a stub. XHCI_SSIC_PORT_UNUSED is added in its
place — it has both a PCI association and a consumer site.
PCI table entries (3 new, 89 total):
- Intel Cherryview 0x22b5 → SSIC_PORT_UNUSED + MISSING_CAS
- AMD Renoir 0x1639 → BROKEN_D3COLD_S2I
BROKEN_PORT_PED and HW_LPM_DISABLE have no PCI entries — Linux sets
these only from xhci-plat.c / xhci-mtk.c / xhci-histb.c (non-PCI host
adapters). They are defined for forward-compatibility with future
platform xHCI support.
xhcid consumer wiring (in local/sources/base submodule):
- log_unenforced_xhci_quirks() called from Xhci::init() emits a
warn! line for each set-but-unenforced R6 flag, citing the Linux
consumer site and the missing Red Bear code path. Observability,
not fake enforcement.
- Real enforcement for consumer sites that require suspend, LPM,
port-disable, or CAS code paths in xhcid is deferred to Phase R8
(PM infrastructure) and follow-up work.
Tests: 8 new (75 → 83 total passing).
Clippy: 26 warnings, all pre-existing R0–R5 baseline. No new warnings.
TOML validator: 244 entries, 0 undefined (no TOML changes for R6 —
xHCI controller flags are compiled-in only).
Source of truth: Linux 7.1 drivers/usb/host/{xhci.h, xhci-pci.c,
xhci.c, xhci-hub.c, xhci-plat.c, xhci-mtk.c, xhci-histb.c}.
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.