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>
fault-ap-df pins a #DF to an AP (its own IST must catch it); affinity checks a pinned task never migrates. onException now names the core, so an AP fault is attributed and shown contained. Both teeth-checked.
Add a discovery case (asserts stable ACPI/MADT/FADT/AML facts) and a wx case (audits R+X code vs NX data/rodata/heap/stack via arch.pageExecutable). Wire the existing poweroff/reboot cases into the harness. Suite: 18 -> 22.
Adds paging.isExecutable and arch.trampolinePage; the smp case now asserts the frame is zeroed and non-executable after bring-up. Teeth-checked against a no-op disarm.
Daniel SamsonandClaude Fable 5
daniel