Red Bear OS — microkernel OS in Rust, based on Redox

Derivative of Redox OS (https://www.redox-os.org) adding:
- AMD GPU driver (amdgpu) via LinuxKPI compat layer
- ext4 filesystem support (ext4d scheme daemon)
- ACPI fixes for AMD bare metal (x2APIC, DMAR, IVRS, MCFG)
- Custom branding (hostname, os-release, boot identity)

Build system is full upstream Redox with RBOS overlay in local/.
Patches for kernel, base, and relibc are symlinked from local/patches/
and protected from make clean/distclean. Custom recipes live in
local/recipes/ with symlinks into the recipes/ search path.

Build:  make all CONFIG_NAME=redbear-full
Sync:   ./local/scripts/sync-upstream.sh

scripts/network-boot.sh

@@ -0,0 +1,52 @@
+#!/usr/bin/env bash
+
+# Your host must use the static IP ${NETWORK}.1 and subnet mask 255.255.255.0
+# 'Rx' in ascii is 82 and 120, adjust to taste
+NETWORK=10.82.120
+
+set -ex
+
+trap 'kill -HUP 0' EXIT
+
+eval $(make setenv)
+make "${BUILD}/rbos-live.iso"
+
+echo "Allowing packet forwarding"
+echo 1 | sudo tee /proc/sys/net/ipv4/ip_forward
+
+iface="$(route | grep '^default ' | grep -o '[^ ]*$' | head -n 1)"
+echo "Forwarding packets to '$iface'"
+if ! sudo iptables -t nat -C POSTROUTING -o "$iface" -j MASQUERADE
+then
+    echo "Forwarding rule does not exist, adding"
+    sudo iptables -t nat -A POSTROUTING -o "$iface" -j MASQUERADE
+else
+    echo "Forwarding rule already exists"
+fi
+
+ARGS=(
+    "--no-daemon"
+    "--bind-interfaces"
+    "--listen-address=${NETWORK}.1"
+    "--port=0"
+    "--dhcp-range=${NETWORK}.3,${NETWORK}.254,255.255.255.0,1h"
+    "--dhcp-option=6,1.1.1.1,1.0.0.1"
+    "--enable-tftp"
+    "--tftp-root=$(realpath "${BUILD}")"
+    # BIOS
+    "--dhcp-match=set:bios,option:client-arch,0"
+    "--dhcp-boot=tag:!ipxe,tag:bios,undionly.kpxe"
+    # EFI x86_64
+    "--dhcp-match=set:efi-x86_64,option:client-arch,7"
+    "--dhcp-match=set:efi-x86_64,option:client-arch,9"
+    "--dhcp-boot=tag:!ipxe,tag:efi-x86_64,ipxe-x86_64.efi"
+    # EFI aarch64
+    "--dhcp-match=set:efi-aarch64,option:client-arch,11"
+    "--dhcp-boot=tag:!ipxe,tag:efi-aarch64,ipxe-aarch64.efi"
+    # IPXE
+    "--dhcp-userclass=set:ipxe,iPXE"
+    "--dhcp-boot=tag:ipxe,rbos.ipxe"
+)
+
+sudo dnsmasq "${ARGS[@]}"&
+python3 -m http.server -b "${NETWORK}.1" -d "${BUILD}" "8080"