Scope decided with Captain Bob before implementation: ring buffer +
recall on today's full-screen vt100 grid, not also confining REPL text
to the 4.4o 640x480 box (that confinement stays open as its own future
item, not a third silent deferral). No keyboard input path exists yet
(M8 unstarted), so the trigger is two new FORTH words, SCROLL-BACK
( n -- ) / SCROLL-FWD ( n -- ), exercised via serial injection.
vt100.c gains a text-only 1000-line ring buffer (kmalloc'd, tens of KB
-- not pixel snapshots, which would be ~1000x larger for no benefit)
plus a shadow buffer mirroring the current screen. scroll_up() now
pushes evicted rows into the ring before the pixel scroll. History is
one continuous sequence (ring then shadow); scrolling always redraws
from that sequence -- no separate pixel-scroll path for scrollback,
decided up front to avoid retrofitting later.
New src/word_source/scroll_words.c (Module 31), thin wrappers over
console_fb_scroll_back()/_fwd() -> vt100_scroll_back()/_fwd(). Bug
caught during live testing: both words initially used an off-by-one
underflow check (dsp < 1) copied from a different, older dsp
convention elsewhere in this codebase; vm_pop() (which these words
actually call) uses dsp as a 0-based top-of-stack index, so the check
rejected every legitimate single-argument call. Fixed by removing the
separate precheck and relying on vm_pop()'s own guard.
Live-verified on all three architectures (exceeds this item's
amd64-minimum bar): generated 50+ lines via a FORTH loop, confirmed
SCROLL-BACK recovers correctly older content, and on amd64 confirmed
SCROLL-FWD returns to genuinely live state (not a frozen snapshot) by
showing the injected commands' own echo. Known limitation confirmed by
direct pixel measurement: redrawn lines lose their original SGR color
(not stored per-cell) -- text recovers exactly, color does not.
Three-arch verified: Failed: 0, dict-hashes identical across all
three (values changed correctly from prior items -- two new words
were added).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Verification only, no permanent code (matches this item's own title
and 4.4i's same-shape precedent -- 4.4l-4.4o were geometry decisions,
not drawing code). One-shot diagnostic probe in sk_repl() drew 4.4o's
box outline plus a strip-top marker, then was reverted after capture
per this document's write/run-once/capture/revert discipline.
Measured pixel bounds directly from each screendump (not eyeballed)
and confirmed exact matches against 4.4o's computed coordinates on
all three architectures: amd64 box x:[320,959] y:[104,583], strip
marker y:704; aarch64/riscv64 box x:[80,719] y:[4,483], strip marker
y:504.
Observed, not fixed here: on the small architectures the REPL banner
text visibly overlaps the box's top edge, because vt100's cursor grid
still spans the whole screen rather than being confined to the 96px
strip -- a real gap between the landed REPL path and the mockup,
belongs to 4.4q/4.4r's wiring work, not this item.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Pure geometry, no code change. Blocking question checked first: both
4.4n CANVAS heights (688px amd64, 488px aarch64/riscv64) clear the
480px minimum, so no architecture fails the fit.
amd64: box raster top-left (320,104), 320px side margins, 104px
top/bottom margins.
aarch64/riscv64: box raster top-left (80,4), 80px side margins, 4px
top/bottom margins (confirms 4.4n's 16px gap choice lands exactly
where predicted).
Also translated both into TTF-TEXT's Cartesian bottom-left-origin
convention for whatever later item issues the actual TTF-TEXT calls:
amd64 bottom-left (320,216), aarch64/riscv64 bottom-left (80,116).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Pure geometry, no code change. Gap chosen at 16px, within 4.4m's
flagged <=24px ceiling for the 600px-tall architectures, leaving 8px
of margin rather than cutting to the exact limit.
amd64 (1280x800): CANVAS top-left (0,0), 1280x688, strip at (0,704)
96px tall.
aarch64/riscv64 (800x600): CANVAS top-left (0,0), 800x488, strip at
(0,504) 96px tall.
Checked against 4.4o's 480px scroll-box requirement: 488px clears it
with exactly the 8px margin the gap choice was picked to preserve.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Design decision, no code change (4.4j's constants are already the
final values). Text size 20px (unchanged from 4.4j), 4 visible lines,
strip height 96px (4 x the existing 24px cell height, no extra
padding -- leading is already baked into that cell height).
Flagged the constraint this feeds into before deciding: 4.4o needs a
640x480 scroll-box to fit inside CANVAS on the 600px-tall
aarch64/riscv64 screens, which only leaves 24px of slack over the
480px minimum once the 96px strip is subtracted. 4.4n's gap choice
must stay <=24px on those architectures or 4.4o's fit check fails --
recorded now so it's not a surprise two items later.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Investigation only, no code change. Answered incidentally by 4.4k's
screendumps rather than requiring a separate run: amd64 1280x800
(QEMU/OVMF GOP default), aarch64 and riscv64 both 800x600 (-device
ramfb's default). Two different resolutions across the fleet, not
three uniform ones -- flagged for 4.4n/4.4o's CANVAS geometry work,
which needs to branch per architecture rather than assume one shared
screen size.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
No code changes -- investigation/verification only. Injected a raw SGR
escape sequence over the serial socket at the ok> prompt (composed from
EMIT + ." since no FORTH word emits a literal ESC byte + text
directly): 27 EMIT ." [95mCOLOR-TEST" 27 EMIT ." [39m", bright magenta
(the p>=90&&p<=97 branch in apply_sgr()), a third SGR code path
distinct from 4.4h's already-verified truecolor prompt.
Screendump on all three architectures confirms COLOR-TEST renders in
bright magenta via the 4.4j-retargeted TTF draw call, proving the SGR
parser and the new glyph backend work together end-to-end, not just
independently. First screendump evidence ever captured for
aarch64/riscv64 in this document -- every prior screendump item was
amd64-only with that gap explicitly accepted; incidentally closed here
via the QEMU monitor screendump command against each arch's own
display device (ramfb for aarch64/riscv64). Both confirmed booting at
800x600.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
font_8x16.c keeps rendering everything through and including POST;
TTF-TEXT's rasterizer takes over at the interactive REPL boundary
(sk_repl()) via a new runtime mode switch, vt100_enable_ttf()
(console_fb_enable_ttf() wrapper), not a compile-time swap -- both
backends coexist in the same binary since boot/POST must stay
font_8x16.c per this item's own done-when.
TTF-TEXT (the FORTH word) isn't directly callable from vt100.c -- VM
stack arguments, different call shape than a one-glyph cell draw. Used
hal/ttf.c's VM-independent primitives directly instead (same rasterizer
TTF-TEXT itself calls underneath), added as a native C helper in
vt100.c. Lazily loads fonts:JetBrainsMono-Regular.ttf and kmallocs a
96-slot raster cache (covers all 95 printable ASCII, no eviction
thrash) on first switch.
Cell geometry changes at the switch (mode-aware cell_w()/cell_h()):
provisional 12x24 TTF cell (600/1000em * 20px = 12px exactly, using
4.4i's confirmed-uniform hmtx advance width) vs font_8x16's fixed 8x16
-- cols/rows re-derived and screen cleared at the switch point, same as
vt100_init() itself does. Final REPL text size is 4.4m's decision, not
this item's.
Also fixes the second call site 4.4i flagged: erase_line_range() now
uses one fb_fill_rect() instead of a per-cell font_8x16-specific blank
glyph draw, consistent with erase_display(2)'s full-screen case.
Three-arch verified: amd64/aarch64/riscv64 all reach ok>, POST
Failed: 0, identical dict-hashes. amd64 screendump shows real
proportional JetBrains Mono letterforms on the REPL tail, visibly
distinct from every prior font_8x16 screenshot.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Investigation only, no code change. draw_cursor_glyph() itself is
single-call-site as claimed, but found two things the item's original
framing missed:
1. A second, independent fb_draw_glyph() call site in
erase_line_range() (partial-line/partial-screen erase), inconsistent
with full-screen erase which already uses a pixel fb_fill_rect().
2. fb_cell_w()/fb_cell_h() are hardcoded 8*scale/16*scale literals
matching font_8x16.c specifically, not derived from any generic
font-metric abstraction; UNDERLINE_ROW hardcodes "row 14 of 16" of
that same fixed grid.
So 4.4j has three things to retarget/generalize, not one. Font data
verified directly from JetBrainsMono-Regular.ttf's hmtx table (parsed
by hand, no fontTools available): all 95 printable ASCII glyphs share
one advance width (600/1000 em units) -- genuinely monospace for the
glyphs in use, not just by filename.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
console.c's emit_prefix() now wraps [VMName] (brackets included) in
FABRIC.md 4.4's locked orange (0xFFA500), and repl.c's two "ok> "
call sites send FABRIC.md 4.4's locked cyan (0x55FFFF), both as real
SGR escape sequences through the existing font_8x16.c/vt100.c pipeline
-- 4.4b already established this needs no dependency on TTF-TEXT/4.4j.
Sent through both raw_putc() (serial) and vt100_putc() (framebuffer),
matching the existing dual-path pattern, so an ANSI-aware serial
terminal renders the same colors as the framebuffer.
Three-arch verified: amd64/aarch64/riscv64 all reach ok>, POST
Failed: 0, identical dict-hashes. Color applies correctly to any VM
name (confirmed via the [Hermes]-prefixed PARITY:BIRTH line in all
three logs, not just [Hera]). amd64 screendump confirms the rendered
colors directly.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Moves the console_fb_init() call in kernel_main.c from after
capsule_birth_mama() to before it, so the fleet-birth/self-test
transcript (Hermes x2, Artemis births, Stadium self-tests -- currently
serial-only) is also framebuffer-visible, not just the small post-birth
tail.
4.5f's -O2 experiment already showed this doesn't hang under
optimization, just costs roughly 12x more boot-time heartbeat ticks
(one-shot, paid only during fleet birth, never repeated at runtime).
Captain Bob's call: worth it, since the serial log was never the
problem -- this is about the same transcript also reaching a real
screen.
Three-arch verified: amd64/aarch64/riscv64 all reach ok>, POST
Failed: 0, identical dict-hashes across all three. amd64 screendump
confirms the framebuffer now carries the full transcript.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Uncommitted experiment (code reverted after capture, per Captain Bob):
moved console_fb_init() before capsule_birth_mama() in kernel_main.c,
amd64 only. At -O2 the boot completes cleanly and reaches ok> well
inside a 300s bound, versus the indefinite stall previously seen at
-O0. Real cost: ~12x more heartbeat ticks during boot from the extra
framebuffer scroll volume -- not free, but not a hang.
Screendump confirms the actual point of 4.4g: the framebuffer now
carries the full HADES/ECW/Stadium/self-test transcript, not just the
small post-birth tail.
This informs 4.4g's open reorder decision, it doesn't make it -- 4.5f
stays unchecked (single-arch feasibility check only, not the three-arch
acceptance pass its own done-when requires).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
FABRIC.md item 4.5d Finding 4: lidt()'s inline asm used a register-only
("r") constraint on the idtr pointer, never telling GCC the asm
dereferences the pointee. At -O2 this let the compiler treat the
256-entry idt[] population loop and idtr_desc's field writes as dead
stores and eliminate them entirely, loading IDTR from uninitialized
stack instead of the real table -- a #GP on the first APIC timer tick
that happened to land on garbage. Same bug class as the earlier
muldiv64 fix (b43e51a): an inline-asm constraint too weak for what the
asm actually touches, invisible at -O0, live at -O2.
Fixed by switching to a memory operand ("m"(*idtr_desc)), matching how
Linux's own load_idt() is written. aarch64/riscv64 checked for the same
pattern -- neither has it, both install their vector/trap tables
entirely in hand-written .S.
Verified: all three architectures boot clean to ok>, POST Failed: 0,
identical dict-hashes across all three under -O2, zero new warnings
vs an -O0 baseline (amd64 3040/3040, aarch64 3041/3041 serial,
riscv64 3037/3037). -O2/-U_FORTIFY_SOURCE landed permanently in
COMMON_CFLAGS.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Computed the loader's true runtime relocation delta to correctly correlate
fault addresses (the running image is starkernel_loader.efi, a relocated
PE, not the separately-linked starkernel_kernel.elf assumed at first).
Fault RIP decodes to log_message()'s entry -- coincidental, not causal,
since it's called on nearly every HADES dispatch during word registration.
Used QEMU's monitor for -d exec,int tracing. Late-start tracing (stop right
before the danger zone to keep trace size down) failed twice -- the window
between a detectable checkpoint and the crash is shorter than host-side
reaction latency. Fell back to full-boot tracing from -S (~2.7GB per
attempt, not committed). That trace shows an unremarkable, normal-looking
repeating three-block loop immediately before the fault, then "Servicing
hardware INT=0x20" (APIC_TIMER_VECTOR) with IDT already showing limit=0 at
that instant.
Ruled out a second illegitimate lidt call (only one call site exists
anywhere, one-time M4 boot setup; searched the trace for any later
execution of that address range and found none). Not yet established: the
actual corrupting write. Documented two remaining explanations (earlier
silent corruption vs. a genuine TCG artifact) and that pinpointing the
exact instruction needs GDB-level single-stepping, a bigger tooling step
than attempted this session.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Used QEMU-side instrumentation (-d int tracing, plus a working chardev-based
monitor -- the older bareword -monitor syntax silently fails on QEMU
10.2.1) as directed. The PM Timer "stall" was never a hang: it was a #DE
divide error cascading to a triple fault, which -no-reboot converts into a
silent clean QEMU exit -- indistinguishable from a hang without tracing,
and why arch_relax() (solving a hang that didn't exist) had no effect.
Root cause and fix documented in full (also see commit b43e51a).
With the fix, amd64 boot at -O2 now proceeds far past the original stall --
through capsule birth and into Hermes's word registration -- before hitting
a second, different fault (Finding 4): a direct #GP at IDT index 32
(APIC_TIMER_VECTOR), not yet root-caused. Same silent-triple-fault-exit
shape, so this was very likely bundled into "the hang" before tracing
distinguished the two separate bugs.
-O2 reverted again (uncommitted); muldiv64's fix is kept, real and
independently verified at unchanged -O0 on all three architectures.
Routine three-arch artifacts from this session's verification runs
included.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
FABRIC.md item 4.5d: root-caused the -O2 boot stall via QEMU '-d int'
tracing -- not a hang. It's a genuine divide-error (#DE) cascading through
a double fault into a triple fault, which -no-reboot converts into a
silent, clean QEMU exit (indistinguishable from a hang without tracing).
muldiv64()'s inline asm declared RDX as a plain output ("=d"(hi)), which
only tells GCC "I want RDX's value after this block" -- nothing told it
that mulq writes RDX *before* divq needs to read a *different* value (the
divisor c) out of it. Nothing stopped the register allocator from placing
c itself in RDX, which mulq then overwrites with the product's high 64
bits before divq ever reads it. Confirmed via the fault's register state:
RAX=0xe8d4a51000 (=1000*1e9 exactly, product fits in the low 64 bits, so
mulq's high-word output is 0) -- if c got allocated to RDX, divq then
divides by that corrupted 0, exactly matching #DE. Worked by accident at
-O0 (different, more conservative allocation); -O2 actually hit it.
A unsigned __int128 rewrite was tried first but needs libgcc's __udivti3
for the general 128-bit case, undefined in this freestanding build -- not
viable, same class of problem as the earlier putc/getc finding. Fixed
instead by declaring rdx a pure clobber rather than an output, the same
pattern the Linux kernel's own mul_u64_u64_div_u64 uses -- a clobber tells
GCC the register is used internally for the whole block and must never be
allocated to any operand, which is the guarantee the previous constraint
list was missing.
Also added a defensive end_tsc<start_tsc guard in the caller
(calibrate_tsc_with_pmtimer): this file's own comments already flag TSC
non-monotonicity as a real risk under TCG hypervisor mode, and an
underflowed delta_tsc would hit the same class of quotient-overflow #DE.
Not the bug that was found, but a real latent risk given what this
function's own documentation already says about the environment.
Verified: with -O2 (uncommitted, not yet reintroduced) this specific stall
is gone -- boot now proceeds far past this point, through capsule birth
and into Hermes's word registration, before hitting a second, different,
not-yet-root-caused fault (write-up follows). Three-arch acceptance boot
clean at unchanged -O0 (this fix doesn't change -O0 behavior, only
prevents UB that only manifested under optimization).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Follow-up probing narrowed Finding 3's behavior (inconsistent stall point
run-to-run: sometimes reaches iters=1000/delta=951 before stopping,
sometimes never gets past iters=0 even after a 400-second bounded wait) but
didn't pin the mechanism.
Tested the strongest available hypothesis: single-threaded TCG scheduling
starvation from an -O2-tightened spin loop, based on a real precedent --
calibrate_apic_timer() (apic.c) already calls arch_relax() every iteration
of its own spin-wait; calibrate_tsc_with_pmtimer() never had it. Added the
same call, matching that precedent exactly. Result: no change, same exact
stall point on a fresh 60-second bounded wait. Reverted.
Stopping here per this document's own §25.0 rule 5 -- root-causing further
needs either deeper TCG/QEMU internals knowledge or a different diagnostic
approach (host-side instrumentation) than another guess-and-check pass.
Makefile.starkernel and timer.c both back to committed -O0 state, confirmed
booting clean.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Finding 2 (putc/getc) fixed via shim.c backfill (previous commit). With
both Finding 1 (-U_FORTIFY_SOURCE) and Finding 2 fixed, amd64 links clean
at -O2 -- rigorously confirmed zero new warnings by diffing normalized
warning text between -O0 and -O2 builds (empty diff, ~3040 pre-existing
warnings in vendored code unchanged).
New Finding 3, not fixed, now blocking: amd64 boot stalls for minutes
inside calibrate_tsc_with_pmtimer() (timer.c:560-589) at -O2 -- a
mainline busy-wait loop reading the ACPI PM Timer via genuinely-volatile
inl() until 1000 real ticks elapse, bounded by a 5M-iteration timeout. A
one-shot diagnostic probe (reverted after capture) caught exactly one
checkpoint in 55 seconds of observation, then nothing -- not yet
root-caused whether this is the 5M-iteration timeout itself taking several
minutes to exhaust under -O2, or a genuine non-terminating condition.
Makefile.starkernel reverted to -O0 again; nothing broken landed in
history. Routine artifacts from this session's boot attempts included.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
FABRIC.md item 4.5d: GCC's -O2 folds putchar(c)/fputc(c,stdout) call sites
into putc(c,stdout), and getchar() into getc(stdin) -- neither symbol was
ever needed at -O0 because that fold pass is inactive there. Both are thin
wrappers reusing the existing putchar()/getchar() implementations exactly
(putc -> console_putc via putchar; getc -> the existing "no stdin in
kernel" -1/EOF stub via getchar), not new behavior.
Harmless at the current -O0 build (nothing calls these symbols directly at
-O0); this is prep for enabling optimization, verified against a clean
amd64 boot at unchanged -O0.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Attempting -O2 on amd64 surfaced two link-time findings, neither of which
was warnings the way 4.5d's own text anticipated:
1. Fixed: -O2 broke the link with __printf_chk/__memset_chk/__fread_chk/
__snprintf_chk undefined references across five vendored word_source
files. Root cause: those files unconditionally #include real glibc
headers (no __STARKERNEL__ guard), which under Ubuntu's default
_FORTIFY_SOURCE and -O2's __OPTIMIZE__ rewrite printf/etc. call sites to
_chk variants that shim.c's freestanding backfill never provided --
worked by accident at -O0 where the macros stay dormant. Fixed by adding
-U_FORTIFY_SOURCE, the standard fix for this exact situation in
freestanding/kernel builds.
2. Not fixed, blocking: with fortification disabled, plain putc/getc turned
up as genuinely undefined -- shim.c never backfilled those, only printf/
snprintf. -O0 doesn't need these symbols for reasons not fully
established (GCC's -O2 function-splitting visibly clones at least one
call site); this needs a real design decision (backfill shim.c vs. guard
the call sites out of __STARKERNEL__ builds), not a mechanical flag.
Makefile.starkernel reverted to the committed -O0 state (the -O2 change was
uncommitted, so a plain git restore -- nothing broken landed in history).
4.5d stays open pending Finding 2's resolution.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
-O2 over -O1/-Og: no optimization level has a verified track record here,
so pick the one that actually solves the motivating problem (4.4g's
fb_scroll_rows() stall needs real loop batching -Og doesn't reliably do)
and matches what both sibling Makefiles already default to.
No LTO yet: deliberately deferred, not rejected -- stacking a second risky
change (LTO, which CLAUDE.md already documents has broken this exact
codebase before) on top of a first-ever optimization pass would make any
4.5e failure ambiguous between two causes. Isolate them.
No -DNDEBUG: checked, not assumed. Zero runtime assert() calls exist
anywhere in the kernel build -- the two "assert(" hits found are a
_Static_assert pair (compile-time, ungated regardless) and a comment. The
freestanding assert.h shim is itself unconditional and ignores NDEBUG too.
Nothing for the flag to affect; copying it by habit would have been exactly
the cargo-culting this item warned against.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Marks 4.5b done with the verification record (three log dirs, all reaching
[Hera] ok> at unchanged -O0). Routine artifacts from this session's
three-arch runs: capsules/BLOCK_MAP.md, disk/artemis.img, DOE CSVs, QEMU
serial logs.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Written directly in ISR context on all three architectures
(heartbeat_tick(), heartbeat.c:163) and read directly by mainline
(heartbeat_ticks(), including the busy-wait at kernel_main.c:880) without
being volatile -- worked by accident at -O0, would be a real bug once the
kernel builds with optimization (item 4.5). Every other field in this
struct is mainline-only (heartbeat_service()'s deferred window/variance/
trust processing), so only this one field needed the qualifier.
Punch list item 4.5b complete.
Three-arch acceptance boot clean at unchanged -O0 (no behavior change
intended yet -- this is prep for enabling optimization, not the switch
itself).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Read every interrupt/exception vector handler on amd64, aarch64, and
riscv64, and every global or static variable each one touches directly or
through a called function, checked against its volatile declaration.
One confirmed hazard, matching what 4.5 already reported: TimeTrustState.
ticks is written in ISR context on all three architectures and read by
mainline (including a busy-wait) without being volatile.
Everything else checked out for one of three reasons, each verified by
reading the actual read/write sites rather than assumed: already correctly
volatile (g_sk_fault_word, g_spurious_count, g_plic_claim_count, the
heartbeat.c top/bottom-half handoff, i8042.c's ring buffer, virtio_input.c's
diagnostic counters); write-once during init then single-context for the
rest of boot, so never actually concurrent (each arch's timer-calibration
state, virtio_input.c's device-routing globals); or ISR-reachable only on
the fatal exception path, which halts the core permanently afterward so
there's no return to mainline to race with (console/framebuffer state).
Full findings recorded in FABRIC.md as 4.5a's inventory. No code changed --
investigation only, per the item's own scope.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Captain Bob 2026-08-11: no other item gets worked until 4.5a-4.5f (the
-O0-kernel fix) are done.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Captain Bob: the -O0-kernel finding (with its 4.5a-4.5f scoping) takes
priority over Artemis-last, so it moves up to 4.5 and Artemis moves down
to 4.6. Updated the three other places in this document that referenced
"the 4.5 Artemis boundary" by number to point at 4.6 instead, with a note
on the renumbering history for anyone reading those passages later.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Scoping only, per Captain Bob's explicit instruction -- nothing implemented.
Breaks the -O0-kernel finding into six sequential, individually-committable
items matching this document's §25.0 rule-1 discipline (same treatment 4.4
itself got before 4.4a onward):
4.6a full ISR-global volatile audit (investigation only), 4.6b fix whatever
4.6a finds (starting from the one already-confirmed TimeTrustState.ticks
hazard), 4.6c decide the actual -O flags and record the reasoning before
touching the Makefile, 4.6d apply them and get a clean three-arch build,
4.6e the real three-arch acceptance boot (a kernel that has only ever run
at -O0 has no track record at any other level), 4.6f retry 4.4g's reorder
now that optimization exists to make it viable.
Also flagged, not scoped: the ACL-RWT DoE campaign's overhead numbers were
all measured at -O0; nobody has asked whether they still hold once the
kernel builds differently.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Attempted 4.4g's console_fb_init() reorder twice this session: once bare,
once with the fb_scroll_rows() volatile fix applied. Both stalled boot
indefinitely (12,000+ lines logged, still running after 3 minutes vs. a
normal few-second boot) instead of completing. Root cause traced past the
scroll fix to Makefile.starkernel building the kernel at -O0 -- no
optimization flag has ever been configured there, verified against the
file's full git history (17 commits, only ever one unrelated host-tool -O2
line). Both the kernel's own vendored hosted Makefile and the standalone
StarForth repo's Makefile default to -O2 (up to -O3/-flto on faster
targets); Makefile.starkernel was written fresh for the bare-metal target
and never got that ladder.
Documented as new item 4.6: enabling optimization is not a safe drop-in
change on its own. Found one confirmed, isolated correctness hazard first --
TimeTrustState.ticks (timer.h:90) is written directly in ISR context on all
three architectures (heartbeat.c:163) and read directly by mainline
(heartbeat.c:200-202, including a busy-wait in kernel_main.c:880) without
being volatile, unlike every other ISR-shared global checked
(g_spurious_count, g_plic_claim_count, g_pending_counter/g_pending_valid/
g_adaptive_period_ns are all correctly volatile already). Reverted the
console_fb_init() reorder itself (uncommitted, so a plain git restore) --
4.4g stays open pending 4.6.
Both the reorder attempts' logs (stalled, never reached ok>) and this
session's routine three-arch artifacts (capsules/BLOCK_MAP.md, disk/
artemis.img, DOE CSV) are committed as audit trail per CLAUDE.md.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Found while investigating item 4.4g's boot stall (moving console_fb_init()
earlier caused a >3-minute hang scrolling the fleet-birth transcript). The
GOP framebuffer is mapped write-back RAM (vmm.c:350-363), not
cache-disabled MMIO with side effects, so there's no correctness reason for
the scroll/fill loops to force one un-batchable volatile access per pixel.
g_fb.base stays volatile for other call sites; this function now casts to a
plain pointer for its bulk copy only.
Confirmed this alone does not fix the 4.4g stall -- the kernel builds at
-O0 (no optimization flag anywhere in Makefile.starkernel), so nothing
here gets vectorized regardless of the qualifier. That's now documented as
its own item, FABRIC.md 4.6. Keeping this fix regardless: it's correct on
its own terms independent of 4.4g's outcome.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Three-arch acceptance boot (amd64/aarch64/riscv64) clean, all reaching
[Hera] ok>, plus amd64 screendump evidence for each item -- checking off
4.4c (console_fb_init wiring), 4.4d ([VMName] prefix reaching the
framebuffer), 4.4e (\r/\n fix), and 4.4f (glyph-flip fix, previous commit).
Screendump verification itself stays amd64-only pending future
aarch64/riscv64 screendump tooling; Captain Bob accepted that gap as
non-blocking for these checkboxes.
4.4g reframed from "anomaly, not root-caused" to a design decision: traced
the missing hundreds of lines of boot output to console_fb_init() running
after capsule_birth_mama() (which births the whole Tripod fleet and their
self-tests) rather than before it, so that output is serial-only by
construction -- not a scroll/CSI-parser bug. Left unchecked pending a call
on whether to reorder console_fb_init() earlier in boot.
Also commits routine artifacts from this session's three-arch runs:
capsules/BLOCK_MAP.md (regenerated manifest), disk/artemis.img (Artemis
writes on every boot), DOE CSVs, and the corresponding QEMU serial logs.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
font_8x16_data stores each glyph's 16 scanline bytes bottom-to-top, not
top-to-bottom -- confirmed by hand-decoding 'A' (0x41) and 'T' (0x54): both
only produce their correct letterform when the row order is reversed.
fb_draw_glyph() mapped glyph row 0 to the cell's top pixel row, which was
wrong for this table. Flip the row-to-pixel mapping instead of touching the
4096-byte font data; every glyph now renders right-side up.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
fb_draw_orientation_test() was a one-time diagnostic for 4.3.1 (raw GOP
framebuffer wiring), already [x] done. With 4.4c's vt100 console now live,
the corner blocks just obscure real console output in every screendump.
Function definition left in framebuffer.c/framebuffer.h for future reuse;
only the boot-time call site is removed.
Also commits routine log/manifest housekeeping: capsules/BLOCK_MAP.md
(regenerated by mkcapsule on each build), the amd64 probe logs from before
today's outage, and the screendump logs + evidence screenshot from this
session's 4.4c/4.4d/4.4e verification.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
4.4c/4.4d's fix was screendump-verified on amd64: the framebuffer console
mechanism works and [VMName] genuinely reaches the screen for the first
time. Verifying that screendump surfaced three more issues, each given its
own item per SS25.0 rule 3 rather than folded in silently:
- 4.4e (fixed this session, see prior commit): console_putc() forwarded raw
'\n' to vt100_putc() without '\r', corrupting line-start columns.
- 4.4f (open, not root-caused): character glyphs render vertically flipped.
- 4.4g (open, not root-caused): most of the framebuffer stays blank despite
hundreds of lines of boot output that should have scrolled through it.
Confirmed via a second screendump after the 4.4e fix that 4.4f and 4.4g are
both independent of the \r/\n bug -- unchanged before and after.
Added evidence/ as a new tracked location for durable proof screenshots,
distinct from the existing gitignored fb/ (disposable local eyeballing,
per the 2026-08-07 decision to stop tracking it). Linked from the relevant
4.4c/4.4d/4.4e/4.4f/4.4g entries.
4.4c and 4.4d remain unchecked -- their Done-when criteria require a
three-arch screendump match against the serial log, not yet attempted on
aarch64/riscv64.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
console_putc() mirrored raw '\n' to vt100_putc() while raw_putc() (serial
path) auto-injects '\r' before '\n'. vt100_putc()'s '\n' handler only
increments the row, never resets the column, so every line after the first
started at whatever column the previous line ended on instead of column 0 --
confirmed by screendump as diagonal text scatter across the framebuffer.
Latent since this code was written; invisible until 4.4c turned the
framebuffer console on for the first time.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
console_fb_init() (which calls vt100_init()) was never called anywhere in the
boot sequence -- only raw fb_init() ran, so vt100_putc() no-op'd on every
call and no console output (REPL, POST, boot logs) ever reached the
framebuffer, only the corner orientation-test blocks. Replace the raw
fb_init() call in kernel_main_deep() with console_fb_init() so the
framebuffer console actually comes up (4.4c).
emit_prefix() also wrote the "[VMName] " bracket text via raw_putc() only
(serial), never vt100_putc(), so the bracketed VM name never reached the
screen even once the framebuffer console was live. Mirror console_putc()'s
existing serial/framebuffer split there too (4.4d).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Found while screendump-verifying the prefix fix (now 4.4d): kernel_main.c
deliberately never calls console_fb_init(), so vt100_init() never runs and
vt100_putc() no-ops on every call -- no console output has ever reached the
framebuffer, only fb_init()'s own corner self-test blocks. ROADMAP.md's
obsolete M8 section claimed this path was already live; that was never
actually screendump-verified.
Records Captain Bob's stated end goal (2026-08-11): framebuffer console and
serial console must be functional identically. 4.4c wires that in.
Only uncommitted items were renumbered; 4.4/4.4a/4.4b keep their IDs.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Found while scoping color application (now 4.4d): console.c's emit_prefix()
writes [VMName] directly via raw_putc(), serial-only -- it never calls
vt100_putc(), so the bracketed VM name has never actually reached the
framebuffer despite 4.4a's serial-verified "regression: clean" note. Given
its own item (4.4c) per §25.0 rule 3 rather than folded in silently.
Only uncommitted items (old 4.4c-4.4n, none yet [x]) were renumbered;
4.4/4.4a/4.4b keep their IDs since they're already committed. Also fixed one
stale reference in §27.8's narrative that still pointed at the old
CANVAS-geometry item by its pre-breakdown ID (4.4b -> 4.4k).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.4b complete.
Investigation only, no code. draw_cursor_glyph() (vt100.c:125) already
draws through g_vt.fg/g_vt.bg via fb_draw_glyph(), and apply_sgr() already
parses true 24-bit-color SGR (ESC[38;2;R;G;Bm) -- color reaches the screen
today independent of which font renders the glyph. 4.4c can proceed without
waiting on 4.4d/4.4e.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.4a complete.
Removed the manually-built <Name>)ok>/zuse)ok> prompt suffix from
sk_repl_step()/sk_repl_run() -- console.c's console_putc() already emits a
"[VMName] " prefix at line-start, so the old code was double-printing the
name for non-Hera VMs ("[Hermes] Hermes)ok> "). Now prints only "ok> " and
lets the existing prefix supply the bracket. emergency_console/zuse_session
security semantics unchanged, display-only. Verified: all three
architectures boot live to "[Hera] ok>" (logs/20260811-073408 amd64,
logs/20260811-073448 aarch64, logs/20260811-073542 riscv64).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.4 complete.
Design-only, no code. Format [VM name] ok>; ok> reuses existing
FB_ANSI_PALETTE[14] bright cyan (0x55FFFF); [VM name] gets a fresh literal
orange (0xFFA500), since no orange exists in the ANSI palette. Verified: no
implementation, just literal values checked against the existing codebase
constants and written into FABRIC.md for 4.4a/4.4c to consume.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Expands the single 4.4 REPL item into a granular punch list matching the
4.3.5/4.3.6-series style: prompt format+color (4.4-4.4c), VT100 ANSI/SGR
engine retargeted onto TrueType (4.4d-4.4f), CANVAS geometry (4.4g-4.4k),
scrollback+toggle (4.4l-4.4m), and the blocked (user) prompt segment (4.4n).
Corrects the font_8x16/TTF handoff boundary: the embedded VT100 path renders
everything through and including POST (which runs after the capsule/VM
bootstrap, per CLAUDE.md), not just pre-bootstrap M1-M6 messages as
originally scoped -- TTF-TEXT takes over only once POST completes.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
FABRIC.md: renumber Artemis-last boundary 4.4 -> 4.5, add new 4.4 REPL item
(console visual design scoped this session -- CANVAS is one shared region
above the REPL strip, 640x480 scroll box centered within it, stroke font,
ANSI color, VM-identity + ACL-identity prompt segments, ~1000-line
scrollback), linked to repl-mockup.png.
ROADMAP.md: mark M8 section OBSOLETE -- replaced by FABRIC.md 4.4, kept for
history only.
ttf_words.c: TTF-TEXT's y argument now Cartesian (origin bottom-left of the
physical framebuffer, y increasing upward) instead of raw framebuffer
coordinates, translated once via fb_height() - y. Verified via amd64
screendump (logs/20260811-070418/), text renders right-side-up with
increasing y moving up the screen.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Not implementation -- documentation-only. M8 is tracked outside Stadium
(FABRIC.md §27.5), so this scoping lives in docs/lithosananke/ROADMAP.md
rather than as new FABRIC.md 4.3.x items.
Read the code before scoping, not assumed: the REPL already works
interactively over serial (sk_repl_run(), repl.c) with working
backspace/echo, and its on-screen text already renders via the existing
VT100 console (vt100_init()/font_8x16.c) independent of both the stroke
font and TrueType work -- neither was ever a REPL-strip prerequisite.
What's actually missing: sk_readline()'s console_getc() is
serial-UART-only, never touches KEY-EVENT (4.3.5f); KEY/?TERMINAL
(io_words.c) are dead stubs (KEY calls a getchar() hardcoded to EOF in
shim.c, ?TERMINAL always returns false).
Resolved design decisions: minimal US-QWERTY scancode->ASCII layout
with shift-state tracking (KEY-EVENT carries no modifier state today);
merge keyboard into console_getc()'s poll with serial staying a
co-equal source, not replaced (the entire acceptance/DoE harness
injects over the serial socket -- breaking that breaks make qemu,
DOE_INJECT, and every screendump technique used throughout 4.3.x); wire
KEY/?TERMINAL to the same merged source for FORTH-79 compliance;
CANVAS viewport sizing last, since it's presentation not input
plumbing. Extended scancodes, autorepeat-as-character-repeat, arrow-key
history explicitly out of scope for the "minimal" bar.
FABRIC.md's existing "not yet scoped" notes (4.3.5f's landing-point
note, 4.3.7f's closing note) updated to point here rather than
duplicating the design content.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.7f complete. No code changes -- ttf.c/ttf.h/
ttf_words.c unchanged since 4.3.7e; this is verification only, same
posture as 4.3.6g.
Three-arch acceptance boot clean (standard make ARCH=<arch> clean qemu,
run in order, one at a time): all three reached [Hera] ok> cleanly,
logs committed under logs/20260810-231553(amd64)/231640(aarch64)/
231739(riscv64).
One screendump per architecture, identical TTF-TEXT command sequence
(S" Hi 4.3.7e!" 200 200 28 16777215 TTF-TEXT) via monitor-socket +
serial-injection, same pattern as 4.3.7c/e. All three show the string
rendered legibly with correct mixed-case/digit/punctuation glyphs and
identical monospace spacing.
TrueType rendering (4.3.7-4.3.7f) is now complete, adjunct to the
stroke font per §27.7 decision #4. Stopping here before scoping REPL
wiring (M8), per this item's own posture matching 4.3.6g.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.7e complete. New src/word_source/ttf_words.c
registers TTF-TEXT ( c-addr u x y size color -- ): lazily loads the v1
default font capsule + raster cache once, decodes UTF-8 (C
reimplementation mirroring capsules/fabric.4th's DECODE-UTF8 exactly),
looks up each glyph's cached bitmap, blits via fb_put_pixel, advances
the pen by the glyph's real hmtx advance width scaled to pixels.
Necessary plumbing: ttf_parse() now also locates hhea/hmtx, and
ttf_glyph_advance_width() reads a glyph's advance width -- required for
this item's own "proportional spacing correct" acceptance clause, no
advance-width data existed anywhere else in the parser. Verified in
tools/ttftest.c: A/a/0/space all read advance_width=600, correctly
uniform since JetBrainsMono-Regular.ttf is monospace.
(x,y) is raster pixel space (top-left origin, Y-down), deliberately not
the stroke font TEXT's Cartesian Y-up convention -- recorded explicitly
in ttf_words.h, not conflated.
Verified live, amd64, screendump: injected
S" Hi 4.3.7e!" 200 200 28 16777215 TTF-TEXT over a serial socket after
boot, no error, captured a screendump showing the string rendered
legibly with correct mixed-case/digit/punctuation glyphs and even
spacing. TTF-TEXT is this item's permanent deliverable, not a
throwaway probe. Compile-checked clean on all three architectures.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.7d complete. ttf_raster_cache_get() looks up
(font, codepoint, size_px) in a caller-owned fixed slot array, evicting
round-robin once full, rasterizing into a slot on a miss.
Verified live in tools/ttftest.c: an identical (font, 'A', 24px) call
made twice returns was_hit=0 then was_hit=1, and the slot's own hits
counter reads exactly 1 afterward -- checked programmatically. A
different-codepoint call misses again, proving the key actually
discriminates. Wall-clock timing (miss 0.040ms vs hit 0.001ms) is
printed as informational corroboration only, not the load-bearing
check.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Punch list §25 item 4.3.7c complete. ttf_rasterize_glyph() flattens
quadratic-Bezier contours (fixed 8-segment subdivision, matching
CIRCLE/ELLIPSE's fixed-segment precedent) and fills them into a
caller-supplied bitmap via even-odd scanline fill, no AA. A local
signed Q48.16 multiply (q48_smul) handles negative outline coordinates,
since the shared q48_mul/q48_div are unsigned-only.
Verified two ways: tools/ttftest.c's ASCII-art dump + structural checks
for 'A'/'.'/'a', all recognizable and passing; and a live amd64
screendump via a throwaway TTF-PROBE word (loaded the font capsule,
rasterized 'A', blit via fb_put_pixel), showing a clearly legible 'A'
on the CANVAS -- probe reverted immediately after capture, only the
permanent ttf.c/ttf.h rasterizer remains. Compile-checked clean on all
three architectures (hal/*.c wildcard); this item's own acceptance is
the amd64 screendump, not a three-arch boot (that's 4.3.7f).
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
mkcapsule.c already ingests arbitrary non-.4th files as raw byte blobs
(validate_forth_blocks only applies to .4th filenames), so no hex/base64
text-encoding or tool changes are needed -- corrects the design premise
in FABRIC.md's 4.3.7b item text (see the FABRIC.md correction note this
commit carries). ttf_load_from_capsule() resolves the font capsule by
name, validates its content hash, and points ttf_font_t at the capsule
arena bytes directly, zero-copy.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
ttf_glyph_outline() decodes simple-glyph flag/coordinate runs and
recursively resolves composite components into a caller-supplied point/
contour-end buffer, in Q48.16. Composite scale/rotation/skew transforms
are rejected with TTF_ERR_UNSUPPORTED rather than mis-rendered, since the
shared q48_mul/q48_div are unsigned-only; translation-only composites
(the only kind the v1 glyph repertoire uses) apply cleanly via q48_add.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Freestanding C module resolving a Unicode codepoint (cmap format 4) to a
glyph index and its outline header (contour count, bounding box), verified
against an independent from-scratch Python reference reader via
tools/ttftest.c. Not yet wired into the boot path or capsule system.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
