init is now a real scheduled ring-3 process: it prints a heartbeat and
sleeps, forever. The kernel spawns it at boot via spawnProcess (its own
address space, preemption on) and the boot context drops to idle — the
system's steady state is "kernel idle, init alive in ring 3", beating
~1 Hz. Adds the sleep(ms) syscall. The init/process tests are reshaped
around the heartbeat (repeated syscalls, still-alive, two concurrent
processes on distinct address spaces). Pins init to LLD and folds the
.large code model's .ltext/.lrodata/.ldata into the linker script so its
code segment is R+X. Removes the now-dead borrowed-thread ELF loader
(runInitElf); spawnProcess is the one path. Docs updated. Suite 28/28.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The kernel now links at 0xFFFF_FFFF_8000_0000 (code_model .kernel) and
loads low via the linker script's AT() clauses (.text at 1 MiB). A new
asm _start installs a 64 KiB kernel-owned .bss stack — the loader stack
is a low address that goes away with the identity map — and calls the
Zig entry, which reaches boot_info through the physmap. The user-pf test
blob reads the LAPIC through the physmap window (still present|user, ec
0x5). The low identity map still coexists in the kernel's tables as the
safety net. Suite 27/27.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
The self-hosted linker ignores parts of linker.ld (PHDRS, /DISCARD/,
section order). The higher-half move needs the script authoritative.
Suite 27/27 on the LLD build.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Ring 3 works: user GDT descriptors (sysret-ready layout), TSS.rsp0,
U/S-bit user mappings (W^X preserved), an int 0x80 syscall gate with a
mutable trap frame, and a setjmp-style enter/exit path. /sbin/init is a
real freestanding Zig binary built from sbin/, shipped on the ESP,
loaded by the bootloader (BootInfo.init_base/len), validated and mapped
by an in-kernel user-ELF loader, and run at CPL 3 — syscalls: exit,
ping, write. Tests: user, user-pf (U/S isolation proof, error code
0x5), init. Suite 27/27.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
max_cpus, max_tasks, kernel/IST stack sizes, and timer_hz move from scattered constants into one config module. root.zig goes back to being just the boot contract. Values unchanged; any can become a -D build option later.
Daniel SamsonandClaude Fable 5
daniel