MontaukOS binaries could not use thread-local storage: the ELF loader
ignored PT_TLS and no FS base was ever programmed, so any %fs access
(initial-exec/local-exec TLS, e.g. libbfd's _Thread_local error state)
page faulted at address 0. This is the kernel prerequisite for
cc1plus/libstdc++ in the GCC port.
ELF loader: parse PT_TLS and build the main thread's TLS block above
the loaded image (x86-64 variant II ABI: block below the thread
pointer, TP = base + align_up(memsz, align), .tdata copied from the
template, .tbss zeroed, ABI self-pointer stored at [TP]). The
template description is kept on the process for thread spawns.
Scheduler: fsBase per thread, loaded into IA32_FS_BASE at every
dispatch site through a per-CPU cache - TLS-free processes cost one
MSR write per CPU ever, and userspace cannot desync the cache since
CR4.FSGSBASE stays off. SYS_THREAD_SPAWN gives each new thread its
own TLS block copied from the template (allocated from the process
heap; reclaimed at process teardown).
Ships tls-test.elf in the SDK (built by the devkit target): checks
.tdata values, .tbss zeroing, and the %fs:0 self-pointer, exiting
nonzero on failure. Boot-smoke verified; existing TLS-free programs
are unaffected.
Co-Authored-By: Claude Fable 5 <[email protected]>
Groundwork for the GCC driver: a compiler driver must spawn cc1/as/ld
and know whether each stage succeeded.
Kernel: the scheduler keeps an exit-code ledger (pid -> code; pids are
monotonic so entries never alias), published during teardown right
before waiters wake. SYS_EXIT records main()'s return value, SYS_KILL
records 256+SIGKILL, and the exception handler records 256+signal
mapped from the fault vector (#PF/#GP -> SIGSEGV, #DE/FP -> SIGFPE,
#UD -> SIGILL). SYS_WAITPID now returns the code: 0..255 for a normal
exit, 256+signal for a violent death. Process args grow from 256
bytes to 4 KiB (cc1 invocations do not fit in 256), with crt1 now
parsing up to 255 argv entries from a static buffer.
libc: new spawn.h with posix_spawn/posix_spawnp over SYS_SPAWN -
libiberty's pex layer has a posix_spawn backend, so GCC's driver works
without fork. argv is joined into the kernel args string (spaces in
arguments rejected; no kernel quoting), envp is not transferred, and
non-empty file actions fail loudly with ENOTSUP until the kernel can
redirect stdio on spawn. waitpid() now decodes real POSIX status and
the sys/wait.h macros distinguish exited from signaled children.
Shell: prints [exit code N] after nonzero exits and [terminated by
signal N] for killed or crashed children.
Verified on the OS: cat on a missing file reports exit code 1; a
window-close (clean exit 0) stays silent as it should.
Co-Authored-By: Claude Fable 5 <[email protected]>
Add tear-free scanout to the Intel GPU driver: a second kernel-allocated
scanout buffer, DSPASURF flips latched at vblank, and a vblank interrupt
delivered over MSI (Gen 11+ master/display/pipe IRQ chain) with a
monotonic vblank counter and WaitVblank().
Expose it as SYS_FBFLIP (150): index selects the front buffer, -1
queries support, flags bit0 waits for the flip to latch. fb_map() now
maps buffer 1 right after buffer 0 when flipping is available, and
gui::Framebuffer draws to the off-screen buffer and flips with vsync,
falling back to the direct copy when unsupported.
Scanout is restored to buffer 0 when the flip-owning process exits and
on panic, so the terminal and panic box never land on the invisible
buffer.
Co-Authored-By: Claude Fable 5 <[email protected]>
The A2DP output is a single unmixed PCM stream. A second process
opening audio while a stream was active would reconfigure the SBC
encoder and media clock under the owner and interleave both apps' PCM
into one ring, garbling playback (e.g. launching DOOM destabilized
Music). Add ClaimOutput/ReleaseOutput pid ownership: the first opener
gets the BT sink, later openers fall back to the HDA mixer, and only
the owner can tear the stream down. The scheduler releases ownership
on process exit so a killed app cannot leak the claim.
Co-Authored-By: Claude Fable 5 <[email protected]>
Deferring the Intel BT firmware download off the boot path made the AX211
bootloader stop answering after the first FC05; even the final synchronous
revert freezes boot, so one of the 'neutral' fixes kept in this diff breaks
the bring-up on its own (candidates: BT-TRACE logging inside TransferCallback,
unconditional interrupt-IN re-queue after error completions on a halted EP,
xHCI interrupt-IN ZLP len fix interacting with HID, InPollContext owner
check). Full history + next experiments in memory notes, 2026-07-05/06.
Co-Authored-By: Claude Fable 5 <[email protected]>
danielandClaude Fable 5