Commit Graph
11 Commits
Author SHA1 Message Date
enricobuehler f373dffb5e chore: migrate the main workspace and pf-vkhdr-layer to edition 2024 (WP20)
The safety half of the rust-safety programme's §8.4: `std::env::set_var`/`remove_var` are
`unsafe fn` in edition 2024, converting the class of bug the programme found the hard way
(the 972af299 environ data race lived in a file with ZERO occurrences of the word
`unsafe`) from invisible to counted and compiler-enforced.

Manifests: [workspace.package] edition 2021→2024, rust-version 1.82→1.85 (the pinned
toolchain is 1.96.0, so no toolchain bump — only the declared floor rises); the 13 crates
pinning `edition = "2021"` literally now inherit it (Trap 1: the root bump alone reaches
only `edition.workspace = true` crates and would have left pf-encode/pf-capture/pf-inject
et al. on 2021 while reading as complete); pf-driver-proto's stale rust-version 1.82 pin
now inherits; pf-vkhdr-layer (a separate workspace, inherits nothing) bumped to 2024. The
four vendored crates (fec-rs, cros-codecs, usbip-sim, the patched ndk) stay on 2021
deliberately — upstream code stays pristine. The excluded usbip-poc standalone PoC is
untouched.

Mechanical, done textually across ALL cfg branches so no platform's half is left behind
(Trap 3 — 44% of the host's unsafe is Windows-only and a one-platform `cargo fix` misses
it): 148 `#[no_mangle]` → `#[unsafe(no_mangle)]` (83 in abi.rs); 12 bare extern blocks →
`unsafe extern`; `gen` is a reserved keyword, so pf-vdisplay's generation stamps
(registry.rs, windows/manager.rs) and the WinUI shell's animation counters rename
gen → generation (internal identifiers only, no serde/wire surface); two
match-ergonomics patterns take the compiler's suggested reference form.

env mutation: every `set_var`/`remove_var` site (20 files) now sits in an `unsafe` block
whose SAFETY comment states the real serialization argument (pf-vdisplay's ENV_LOCK,
CONFIG_DIR_TEST_LOCK, ART_ROOTS_LOCK, vkdecode's gpu_lock, the `--test-threads=1`
contracts of the hardware spikes, or single-threaded startup). Two genuine hazards
surfaced en route — exactly the WP3b-class finds this migration exists to make visible —
and are fixed here:
- windows/service.rs spawned the network-profile warner thread BEFORE `load_host_env()`,
  so a child-spawning thread (child spawn snapshots the env block) was live while
  `set_var` ran in a loop; the load now precedes the spawn.
- pf-console-ui's `fake_home()` re-set HOME outside its OnceLock on EVERY call, so two
  parallel tests could race the write; the set now happens exactly once inside
  `get_or_init`.

cbindgen (Trap 2): 0.29.4 parses `#[unsafe(no_mangle)]` — verified empirically; the
header regenerates byte-identical. The ci.yml drift check could never catch "failed to
regenerate" (build.rs demotes a cbindgen failure to a warning and writes nothing, leaving
the checked-in header untouched and the diff clean), so the step now first asserts the
"punktfunk-core: wrote" line and the absence of "cbindgen failed" (sh -e safe: no `!`
pipeline, no tee-masked exit).

rustfmt: style_edition pinned to 2021 at the root — edition 2024 would otherwise flip the
style edition and reformat ~370 untouched files inside this same commit, burying the
migration diff. The drivers workspace pins its already-current 2024 style. Adopting the
2024 style tree-wide is its own future one-line-plus-reformat commit.

Census: the primary metric moves UP BY DESIGN — 2435 → 2453 operations, unsafe blocks
1534 → 1577, and env_set_var is now a counted category (45 ops). The newly counted env
sites are a truer number, not a regression; baseline snapshot saved as punktfunk-planning
design/rust-safety-census-baseline-2026-08-12-edition-2024.txt. Gate C's env ratchet is
now compiler-enforced (the hygiene-script header says so); the two shrunk file counts
(nvenc_cuda 49→2 via the test helpers, shell/tests 2→1) are lowered in the same commit
per the gate's own rule.

Drop order (the semantic change most likely to bite this codebase): the migration lint
`-W tail-expr-drop-order` reports zero findings on the macOS-visible halves of
pf-encode / pf-zerocopy / pf-capture / pf-frame; the Linux and Windows halves run the
same lint on the gate boxes. The four #[ignore]d alloc/drop-cycle tests on the hardware
boxes remain owed, as before this change.
2026-08-12 16:12:35 +02:00
enricobuehler dfebb9dfbb chore(safety): hoist the unsafe lints into the workspace tables (WP2c hoist)
undocumented_unsafe_blocks joins unsafe_op_in_unsafe_fn in
[workspace.lints], and the ~100 scattered per-file #![deny(...)] attributes
(85 files) are deleted — a new crate, or a new module in an old one, is now
covered on creation rather than on remembering. The per-file form is how
pf-vkhdr-layer, wdk-probe and half of pf-clipboard stayed uncovered.

There are THREE workspaces, so the claim is made three times: the main
Cargo.toml, packaging/windows/drivers (workspace table + [lints]
workspace = true in all seven members), and packaging/windows/pf-vkhdr-layer
(its [lints] table, previous commit). pf-update now opts into workspace
lints; the two vendored member snapshots (cros-codecs, usbip-sim) stay out
deliberately and now both say so.

Newly-covered fallout was two link-sanity tests (pyrowave-sys, libvpl-sys)
— proofs written. Stale prose that claimed the workspace held
unsafe_op_in_unsafe_fn at "warn" (it has been deny) or pointed at the
deleted attributes is corrected.

nvenc_core.rs is carved OUT of the unsafe_op_in_unsafe_fn fence: its
exemption rationale ("raw entry-table calls almost line for line") was
false — the file makes zero FFI calls. Its unsafe surface is C-union writes
whose soundness hangs on which codec arm is active, and its own 4:4:4 note
records the shipped bug (hevcConfig bytes stamped onto an AV1 config) that
per-operation blocks make visible. It now runs the strictest discipline in
the crate: clippy::multiple_unsafe_ops_per_block at deny, one union access
per block, each naming its codec guard.

Verified here: cargo fmt clean in all three workspaces; native clippy
-D warnings clean for everything that compiles on macOS (the three
pre-existing mac-native failures — pf-client-core wol.rs, pf-encode
dead-code/closure-call, probe mic_burst — reproduce on the clean tree).
Linux/Windows legs ride the .25/.133 gate.
2026-08-11 23:26:28 +02:00
enricobuehler d25a20a233 feat(vkdecode): the AV1 rungs meet a second tile for the first time
Every AV1 frame either decode rung has ever been measured against is `tile_cols =
tile_rows = 1`. The vendored vector is single-tile on all 274 of its frames, so every
tile array the conversions fill — `tiles.widths`, `tiles.heights`, the per-tile records
— had only ever been written at index 0, and a conversion that wrote tile 0 and left
the rest zero would pass the whole suite. Our encoder splits 4K into TWO TILE ROWS.

**The fixture.** `lowdelay-3840x2160.ivf.av1`, 261 KB, 60 frames — `punktfunk-host
spike --source synthetic --codec av1 --width 3840 --height 2160 --fps 60 --seconds 1
--bitrate 1` on .21 (NVENC, RTX 5070 Ti), wrapped to IVF with `ffmpeg -f obu … -c copy`
so `common::split_av1_aus` (the vendored parser's own `IvfIterator`) frames it exactly
as it frames the vector, with no second splitter that could disagree.

**4K is not a size choice, it is the only shape with the property.** Measured on the
same box with the same command: 1280x720, 1920x1080 and 2560x1440 all give `tile_cols =
tile_rows = 1`; 3840x2160 gives `tile_cols = 1, tile_rows = 2` with
`width_in_sbs_minus_1 = [59]`, `height_in_sbs_minus_1 = [16, 16]`, and both tiles in ONE
Tile Group OBU. 60 frames instead of 120 pays for the resolution: 261 KB, under both the
282 KB H.264 and 270 KB H.265 low-delay fixtures.

Goldens are libavcodec's software decode, cross-checked between ffmpeg n8.1.2 (Arch
x86_64, libdav1d) and 8.1.1 (Homebrew, macOS arm64, libdav1d) whose 746,496,000-byte raw
outputs are BYTE-IDENTICAL, not merely equal per frame. 60 of 60 digests distinct.

**AV1's frame accounting is asserted, never derived.** The vendored vector is 250
temporal units carrying 274 coded frames of which 24 are hidden; this stream is 60 units,
60 coded, 60 shown, 0 hidden, 0 `show_existing_frame`, 1 key frame. Neither is the
general case, so both parity harnesses now take units / decoded / shown as three
independent parameters instead of computing one from another, and the CPU guard states
all six numbers.

**A CPU gate that needed no hardware at all.** `pic_av1`'s new
`a_two_tile_frame_fills_both_row_entries_and_leaves_the_rest_zero` pins the second row
entry against its OWN `height_in_sbs_minus_1`, requires the two rows to tile the frame
exactly, and requires TWO tile RECORDS out of ONE tile group with rows (0,0) and (1,0) —
the transposition a square grid could never reveal — each spanning real bytes. The
existing one-tile test asserts index 0 is right and `1..` are zero, which a broken
multi-tile conversion also satisfies.

⚠⚠ **This is a file, and on AV1 that distinction has already cost a release.** "250/250
delivered frames bit-identical to libavcodec" was true for the entire period the host was
shipping only the FIRST TILE of every 4K frame: the verification ran against a vendored
file while the truncation lived in packetisation, and the suite stayed green throughout.
This fixture closes the multi-tile gap on the DECODE rungs and closes nothing about
fragmentation, reassembly, loss or AU boundaries — the golden header, both module docs
and the leg docs all say so, at length, so the next reader does not inherit the same
false confidence.

Legs: `low_delay_host_av1_every_frame_hashes_bit_identical_to_libavcodec` on the Vulkan
rung (11 ignored legs now) and on the D3D11VA rung, plus two non-ignored CPU tests.

Verified: 11/11 Vulkan parity legs on .21 (RTX 5070 Ti, 610.57.04), the new one 60/60
bit-identical; workspace clippy `-D warnings` and `cargo fmt --all --check` clean on .21.
2026-08-07 23:09:12 +02:00
enricobuehler f0702f3e06 feat(vkdecode): HEVC's exemption stops being an argument and becomes a vendored stream
`fd6241a2` made HEVC's freedom from the release-ordering defect falsifiable on CPU and
recorded what was still missing: no low-delay HEVC stream was vendored, so the exemption
rested on a structural argument plus one throwaway measurement. This vendors the stream,
and the exemption HELD.

**The fixture.** `lowdelay-640x480.h265`, 270 KB, 120 pictures — `punktfunk-host spike
--source synthetic --codec h265 --width 640 --height 480 --fps 60 --seconds 2 --bitrate 1`
on .21 (NVENC, RTX 5070 Ti, driver 610.57.04). Deliberately the H.264 sibling's resolution
and frame count: the two are then directly comparable, 640 and 480 are both multiples of
MinCbSizeY so there is no conformance window and a hash mismatch can only be decode rather
than readback geometry, and 270 KB sits alongside the 282 KB already accepted for H.264.
Goldens are libavcodec's software decode, cross-checked BIT-IDENTICAL across ffmpeg n8.1.2
(Arch, x86_64) and 8.1.1 (Homebrew, macOS arm64), 120 of 120 digests distinct.

**The exemption held, measured rather than argued.** `sps_max_dec_pic_buffering_minus1 = 4`
against the four pictures 8.3.2 keeps marked in steady state, `sps_max_num_reorder_pics = 0`,
`numRefL0 = 1` — a five-picture DPB filled exactly by four references plus the current
picture. 115 of the 120 access units retire a picture, and `removed ∩ dpb_refs` is **0 of
120**. A 300-picture 1080p stream from the same host reports the same shape: 295
retirements, 0 intersections. It is the encoder and not the resolution, exactly as for
H.264.

**A zero proves nothing on its own, so the fixture is pinned by its counterfactual.**
`test-25fps.h264` reported zero for two milestones while every stream we ship aliased on
99% of its frames. So the guarantee here is not "we looked and it was fine": hand
`plan_to_dxva_h265` the marked DPB as it stood BEFORE `decode_rps` — the mutation a
snapshot move would cause, reconstructed exactly as `dpb_refs(N-1) ∪ {stored(N-1)}` — and
the alias appears on **115 of 120** access units, driven through the real conversion rather
than through planner arithmetic. If a regeneration ever produced a stream that reordered,
or a DPB deeper than its reference count, that 115 collapses to 0 and the tests say so
instead of continuing to pass.

**The two rungs are exempt for different reasons, and the asymmetry is now a gate.** DXVA
binds the whole marked DPB — `RefPicList` is spec-defined that way, and an RFI long-term
anchor has to survive in it — so its exemption really is `H265Planner`'s snapshot ordering,
one call away from being untrue. `plan_to_vk_h265` never reads `dpb_refs` at all:
`pReferenceSlots` is the slots the operation uses, so it binds the current RPS sets, which
`decode_rps` itself derives and which therefore cannot name a picture that same RPS just
dropped. A new test feeds that conversion the identical widened snapshot and asserts
nothing changes, so a future change making the Vulkan rung bind the marked DPB — a
legitimate thing to want, since a *Foll* anchor invisible to the hardware is the RFI
failure shape — fails loudly instead of silently acquiring the defect.

What the Vulkan pixel leg adds is therefore NOT aliasing coverage, and its docs say so:
it is the first HEVC frame either rung has decoded from our own encoder, under a DPB that
retires and reissues a slot on 115 of 120 access units back to back, where the vendored
vector's reordering keeps that eviction slack.

Legs: `low_delay_host_h265_every_frame_hashes_bit_identical_to_libavcodec` on the Vulkan
rung (10 ignored legs now, up from 9) and on the D3D11VA rung, plus three non-ignored CPU
guards that run in ordinary CI.

Verified: 10/10 Vulkan parity legs on .21 (RTX 5070 Ti, 610.57.04), the new one 120/120
bit-identical; workspace clippy `-D warnings` and `cargo fmt --all --check` clean on .21.
2026-08-07 22:53:22 +02:00
enricobuehler 834b244301 fix(client): the H.264 twin was real — every low-delay picture decoded into a surface it predicted from
The AV1 review round flagged the H.264 leg as "plausibly the same defect, traced in
source, not reproduced" and deliberately did not touch it. It is reproduced now, and
it is worse than the AV1 one: it fires on 297 of 300 access units of every stream a
punktfunk host emits, at 720p, 1080p and 2160p alike, on BOTH the DXVA rung and the
Vulkan one.

**Decided on the CPU, no GPU needed.** `H264Planner` snapshots `dpb_refs` in
`begin_picture`, BEFORE `finish_picture` runs 8.2.5's marking and C.4.5.3's bump, so a
picture the sliding window unmarks and the bump then evicts lands in both `dpb_refs`
(which `RefFrameList` is built from) and `dpb.removed`. The conversion released the
whole `removed` list and then assigned the decode target a slot; `SlotMap::assign`
takes the lowest free slot, which is the one just vacated. `CurrPic = N` and
`RefFrameList[k] = N`, in one submission.

The two conditions have to coincide in ONE access unit, and low-delay H.264 is exactly
what makes them: `max_num_reorder_frames = 0` means the evicted picture has already
been output, which is what makes it evictable at all. NVENC seals it by writing
`max_num_ref_frames = 3` ALONGSIDE `max_dec_frame_buffering = 3` — a DPB exactly as
deep as its reference count — so the window unmarks the oldest reference in the very
unit whose bump drops it. The aliased picture is `ref_idx 2` of a three-entry
`num_ref_idx_l0_active` list: addressable by any macroblock, not a spare.

**Why two hardware-proven codecs and four GPUs never saw it.** `test-25fps.h264` is
level 1.3 with no VUI `bitstream_restriction`, so `dpb_limit` falls back to A.3.1's
level ceiling and gives a 7-frame DPB against 2 reference frames — the window unmarks
two units before the bump can evict — and it REORDERS, which keeps an unmarked picture
alive past the unit that unmarked it. Two independent reasons, both properties of that
vector rather than of H.264. It measured zero and passed 250/250 throughout.
`data/lowdelay-640x480.h264` is vendored to close exactly that: our own host's output,
120 pictures, goldens from libavcodec cross-checked bit-identical across two ffmpeg
builds on two architectures.

**The fix is the AV1 fix.** `DecodePlanDxva` and `DecodePlanVk` grow
`release_after_decode`, the conversions hand the removals back instead of applying
them, and the callers release them once the decode op is issued. It costs no slot the
map does not have: `SlotMap::new` allocates `max_dpb_frames + 1` and the DPB never
exceeds `max_dpb_frames`, so a free slot always exists with the whole `removed` list
still held — measured, peak 4 of 4 on the stream that defers on 117 of 120 units.

The Vulkan rung breaks on it in both DPB modes and neither loudly: DISTINCT hands the
aliased reference the same array layer the setup writes; COINCIDE clears
`slot_image[setup]` in the binding sync and the reference then resolves to no bound
image, dropping out of `pReferenceSlots` with a `trace!`. Its deferred release runs on
the FAILURE paths too — the fallible region's Result is held rather than `?`-ed,
because seven exits sat between the conversion and the release and each would have
leaked a slot.

`a_full_dpb_bump_reuses_the_slot_but_the_pool_model_binds_a_fresh_image` asserted the
aliasing as "the planner's normal behaviour": an authored depth-1 stream whose AU1
references the picture it evicts. It now asserts the opposite, which is the defect in
two lines.

New evidence, all of it runnable: the CPU proof pins BOTH numbers (0 on the vector,
117 of 120 on the low-delay stream) so neither can drift silently; the ledger-pressure
test measures the peak; and a low-delay parity leg is added to `pf-vkdecode`'s
`gpu_parity` and `pf-client-core`'s `video_d3d11_native::parity` so both rungs are held
to what they stream rather than only to what they conform to.
2026-08-07 22:09:44 +02:00
enricobuehler cdd1f3efce fix(vkdecode): AV1 is bit-exact — the bug was a use-after-free, not the driver
250/250 frames bit-identical to libavcodec on NVIDIA 610.57.04, and all four
other parity legs (H.264, H.265, Main 10, both four-byte-prefix twins) still
green.

session_av1 built the sequence header, handed pStdSequenceHeader to
vkCreateVideoSessionParametersKHR, and dropped the backing the instant the
call returned — on the documented assumption that Vulkan copies parameter
data before returning. NVIDIA does not. It keeps the pointer and dereferences
pColorConfig when a decode is RECORDED. The freed block became our own next
allocation, whose bytes read back as mono_chrome = 1, and a monochrome frame
skips exactly loop_filter_level[2..3] (AV1 7.14).

That is the whole fingerprint two earlier rounds chased: luma bit-exact,
chroma off by small amounts, and rewriting the chroma levels in the bitstream
changing nothing — the driver read them correctly and then discarded them,
because it believed the stream had no chroma. StoredParamsAv1 now holds the
parameters object and its Std backing in one value, so an object whose
backing is gone is unrepresentable.

The road there is worth recording, because two well-evidenced conclusions
were wrong before this one was right. A software oracle reproduced the
divergence exactly by disabling chroma deblocking, and a GPU probe showed
chroma levels [8,12] and [63,63] producing byte-identical output — which
looked conclusive and was not. libavcodec's own Vulkan AV1 hwaccel is
bit-exact on this same driver, which proved the hardware fine and the defect
ours. ffmpeg never hits it: with VK_KHR_video_maintenance2 it uses inline
session parameters and never creates a parameters object at all.

The proof is direct rather than inferred: a throwaway Vulkan capture layer
dumped both submissions and every byte of our AV1 picture info already
matched libavcodec's, including the loop filter block; only the session
parameters layer differed. Watching the block's address showed correct bytes
at create and our next allocation at decode.

Ruled out on hardware, so nobody re-tests them: filmGrainSupport,
maxCodedExtent, maxDpbSlots/maxActiveReferences, VkVideoDecodeUsageInfoKHR,
the tile-start sentinel, the setup slot's SavedOrderHints, a NULL
pTimingInfo, and heap luck.

Two earlier fixes are confirmed against libavcodec's captured wire bytes and
kept: CDEF secondary strengths carry the coded value rather than the spec's
in-place fixup, and LoopRestorationSize is log2-based. The refuted
driver-ignores-chroma-levels claim is corrected everywhere it was written
down, and that probe test now passes and points at the lifetime of everything
a submission points at before blaming a vendor.

⚠ Adjacent and NOT fixed: session.rs and session_h265.rs drop their Std
backings the same way, and those sets carry embedded pointers too. Both are
measured bit-exact on four drivers, so nothing is known to be wrong — but the
contract now rests on a driver behaviour measured FALSE for AV1 on a shipping
driver. The SAFETY comments asserting it have been corrected; the structure
is deliberately untouched pending its own pass.

Gates: macOS fmt/clippy/336 tests, container clippy -D warnings, all green;
8/8 gpu_parity and 3/3 gpu_smoke legs verified on the RTX 5070 Ti.
2026-08-07 00:39:34 +02:00
enricobuehler 96fc3eca10 test(vkdecode): the AV1 rung finally has pixels to answer to
A parity and smoke harness for AV1, mirroring the H.264 and H.265 legs that
proved those rungs bit-identical to libavcodec on four drivers before either
ran on glass. This was the milestone's largest test gap: the adversarial
review found four blocking defects in the AV1 conversion — flags unset on
274 frames of 274, a units error in LoopRestorationSize, per-reference info
describing the wrong picture, film-grain fields left zero — and every one of
them would have shown on frame 1 of a parity run, while clippy and 164 green
unit tests said nothing at all.

The golden is 250 per-frame SHA-256s in DISPLAY order, not 274. The vector
carries 274 coded frames in 250 temporal units; the 24 extras are hidden
ALTREFs, decoded and referenced but never shown, and the rung delivers what
dpb.outputs names. The count is re-derived from the planner rather than
assumed.

Cross-checked between ffmpeg 8.1.1 on macOS arm64 and 8.0.1 on Linux x86_64,
whose raw outputs are byte-identical — and then against a third party neither
build knows about: the vendored vector ships upstream's own per-frame MD5s,
and re-running those reproduces all 250. The golden agrees with a decode
nobody in this program performed. I reproduced both independently before
committing.

8-bit NV12, traced from the sequence header rather than presumed
(seq_profile 0, high_bitdepth 0, mono_chrome 0), so the P010 scar does not
apply here — and the header says which check to make if a Main 10 golden is
ever added. film_grain_params_present is 0, which is load-bearing: grain
synthesis is part of the Vulkan decode profile, so this golden is only
comparable against a grain-less profile key.

Anti-vacuity is the point of the exercise, so it is structural. The golden
guard asserts the exact count, that every line is a bare digest, and that all
entries are DISTINCT — 250 copies of one digest would let a decoder frozen on
a single frame pass parity. The parity body asserts the golden set and the
access-unit count before it touches hardware, so an IVF reader returning
nothing cannot become "0 frames compared, pass". The agent verified the
guards fire by mutating the golden three ways.

assert_bit_identical now names the FIRST divergent frame, which is what
localises a defect; that improves all six legs, not just AV1.

AV1 has no four-byte-start-code twin, deliberately: OBUs are
length-delimited, so there is no prefix for a driver to mis-skip. Documented
where a reader would otherwise see an omission.

Nothing here has run on a GPU. The harness exists precisely so the four
review defects can be answered by measurement instead of argument.
2026-08-06 22:38:04 +02:00
enricobuehler c91a482b4e test(vkdecode): the ten-bit path finally has pixels
Every golden set in this program was eight-bit. So the strongest thing anyone
could say about ten-bit decode was that a Main10 session BUILDS and streams
clean — which is not the same claim, and is exactly the shape of claim this
program has been burned by. A Main10 stream decoding to garbage logs just as
cleanly: HEVC Main10 on D3D11VA has no per-picture status query at all, and on
the Vulkan side the devices that matter report queryResultStatusSupport=false.
The HDR legs were measuring that the pipe ran, not that the pixels were right.

So: a Main10 vector and its goldens, and a ten-bit leg that runs them.

The vector is 50 frames of 320x240 HEVC Main 10 4:2:0 from libx265 — 48 KB,
generated by a command recorded in the golden file's header along with
everything else needed to regenerate it. The goldens come from libavcodec's
software decoder and were cross-checked between two independent builds on two
architectures (ffmpeg 8.1.1 Homebrew/macOS-arm64 and 8.0.1 Ubuntu/x86_64),
which agreed on all 50.

The goldens are P010, NOT yuv420p10le, and that distinction is the whole
reason this could have quietly gone wrong: P010 puts the ten bits in the HIGH
bits of each little-endian 16-bit word with the low six zeroed, which is what
a D3D11 P010 surface and Vulkan's G10X6_B10X6R10X6_2PLANE_420_UNORM_3PACK16
both contain. Hashing LSB-aligned samples against MSB-aligned ones would fail
on every frame on every driver, for a reason that has nothing to do with
decoding. One golden file therefore serves both native rungs.

The readback is now depth-aware. Its only eight-bit assumption was the second
region's buffer_offset, which is a BYTE offset where the extents around it are
TEXELS — that plus the buffer size are the whole change, because
bufferRowLength = 0 already packs rows at the copy extent. The expected pool
format moved onto the readback so the sizing and the per-frame assertion come
from one source; a readback sized for eight bits that then accepted a ten-bit
frame would hash half a picture and blame the decoder.

A CPU guard asserts the vector really is ten-bit — 4:2:0, both depths
minus8 == 2, 320x240, 50 access units, 50 planned outputs. Without it a
regenerated eight-bit vector would turn the ten-bit leg into a second run of
the eight-bit path wearing a ten-bit name, and it would PASS, because its
goldens would have been regenerated alongside it. That guard is not ignored,
so it runs on macOS and in the container rather than only on the fleet.

Hardware: HEVC Main 10 50/50 bit-identical on NVIDIA 610.43.03 (Linux) and on
the Steam Deck's RADV/VanGogh — first run on both, which also confirms the
P010/3PACK16 layout match rather than assuming it. The four eight-bit legs are
unchanged and still green on both boxes.
2026-08-06 13:32:31 +02:00
enricobuehler 5d0b269e58 test(vkdecode): parity over the start-code form the host actually emits
Both vendored vectors carry three-byte Annex-B start codes throughout. The
real host emits four-byte ones on 100% of access units in both codecs —
1514/1514 H.264 and 1133/1133 HEVC, measured off the M0 NVENC corpus through
the capture hook's own .idx offsets. So every parity verdict this program has
recorded was taken on a prefix form that never ships, and the one form that
does ship was exercised by nothing.

That gap is not hypothetical. Submitting four-byte start codes to
vkCmdDecodeVideoKHR unchanged is exactly what made HEVC unplayable on every
driver tested: drivers are validated on the three-byte form, and a fixed
+3 + 2 skip into a four-byte-prefixed slice reads a nonsense pps_id — the
115 and 119 both NVIDIAs printed. H.264 was never safe here by structure,
only by its vendored encoder's convention, which is why the cure lives in the
shared ring layer and why this coverage is generic over both codecs.

Each codec's parity body now takes its access units as a parameter and runs
twice: once over the vector as it sits, once over the same vector rewritten
to four-byte prefixes. Prefix width carries no information, so both runs must
reproduce the same goldens — sharing one body is what makes that an equality
rather than two assertions that can drift.

The rewrite copies nalu.data[nalu.offset..], the same nal_size bytes the
parser hands the planner, so trailing_zero_8bits are dropped exactly where
the production parser drops them: the only difference between the two streams
is the width of every prefix.

Two CPU guards keep the new legs from passing vacuously, which is the failure
mode they are most exposed to — a rewrite that quietly returned its input
would make them trivially green and nothing on the fleet would notice. They
assert the original really does carry three-byte prefixes, that the rewritten
stream carries none, that the NAL count is preserved exactly, and that the
planner still yields 250 pictures.

Hardware: all four legs 250/250 bit-identical to libavcodec on two
independent driver stacks — AMD VanGogh on RADV/Mesa 26.0-devel (the Steam
Deck) and NVIDIA 610.43.03 on Linux. NVIDIA is the family that rejected the
four-byte form outright, so it is the meaningful witness for this regression.
2026-08-06 12:02:03 +02:00
enricobuehler 5c6b09a5c5 test(vkdecode): the HEVC GPU legs, which find M3 broken on every driver
M3 was recorded as code complete. Its exit criteria named the HEVC gpu_smoke
and gpu_parity legs, and the goldens for them were committed — 250 per-frame
NV12 hashes, cross-checked between two independent FFmpeg builds, with a
header saying they are "consumed the same way by the HEVC parity test". No
such test existed. Both GPU files were H.264 only, with zero references to
h265, so nothing had ever decoded a single HEVC frame through this crate on
hardware.

They exist now, and the first run answered. On AMD Adrenalin 25.10.30.02
(distinct mode, queryResultStatusSupport=false) 247 of 250 frames diverge
from libavcodec, and that device's smoke leg PASSES — because smoke only
reads the driver's verdict and that driver reports none. That is the Ally X
class, reproduced in-house on demand: output that is wrong everywhere the
picture is looked at and clean everywhere the decoder is asked. Both NVIDIA
drivers reject the stream outright and name the cause themselves,
"Invalid PPS/SPS id in slice header (pps_id=119 / 115)" — the identical two
values, and the smoke leg dies at the identical AU 9, on a 4090 under 610.88
on Windows and on an RTX 5070 Ti under 610.43.03 on Linux. Same wrong values,
same access unit, two GPU generations, two operating systems: deterministic,
and therefore ours rather than any driver's.

It is not an ordering fault. Five of the divergent hashes appear nowhere in
the 250 goldens, so the pixels are wrong rather than correct-but-reordered.
Parity dies at frame 1 while smoke dies at AU 9 only because smoke holds four
frames before it looks; the first inter-predicted picture is already corrupt.

The legs are committed ahead of the fix deliberately. They are the regression
test for the defect, they are #[ignore]d so no CI leg changes colour, and the
evidence above is worth recording in the order it was obtained.

Adding a third and fourth copy of ~150 lines of unsafe Vulkan bring-up was
not acceptable, so it moved to tests/common. The two behavioural differences
between the callers are now named parameters rather than accidents: the parity
legs read back on a graphics queue and require one, while the smoke legs
accept a decode-only device and fall back to the decode family — which also
decides whether pool images are EXCLUSIVE or CONCURRENT, so it is load-bearing
rather than cosmetic. H.264 came through the refactor unchanged, verified two
ways: argument-by-argument against the previous file, and on hardware, still
250/250 bit-identical on NVIDIA Windows, AMD Windows and now NVIDIA Linux.

The loader is deliberately leaked at teardown. ash::Entry owns the Arc<Library>,
so dropping it unloads the Vulkan loader with every ICD and implicit layer;
harmless while each binary held one GPU leg, but each now holds two, and the
second would re-open a loader the first had torn down.

Three guards run without a GPU, because everything above is #[ignore]d: the
golden file's count and digest shape, the HEVC access-unit split agreeing with
what the CPU planner emits (with iraps == 1 pinning "no CRA anywhere", so a
re-synced vector that opens with one fails here rather than as a frame-count
mismatch on the fleet), the vector staying Main 4:2:0 8-bit since both legs
hard-code that probe, and a refusal to run the smoke legs with
PF_VKD_TEST_READBACK set, which would quietly grow the pool a usage flag
production never carries.
2026-08-06 09:47:30 +02:00
enricobuehler e6d6498a49 test(pf-vkdecode): frame-hash parity vs libavcodec — bit-exact on the whole fleet
WP-D parity A/B. gpu_parity (ignored) decodes the conformance vector,
reads every frame back through the presenter's exact contract (wait,
layout round-trip, signal-back, release), crops at the copy so pitch
can never leak, and compares SHA-256s in display order against goldens
from ffmpeg software decode — cross-checked bit-identical between
ffmpeg 8.0.1 (linux) and 8.1.1 (macOS), so the reference is the spec,
not one build. PF_VKD_TEST_READBACK=1 is the one test-only hook (ORs
TRANSFER_SRC into pool usage; production pools stay zero-copy-tight).

Fleet verdict: 250/250 frames bit-identical to libavcodec on RADV
(Mesa 26.0.3, distinct), AMD proprietary Windows (25.10.30.02,
distinct) and NVIDIA Windows (610.88, coincide) — H.264 decode is
exactly specified, and the native path meets the spec on every driver
and both DPB arrangements.
2026-08-05 20:23:18 +02:00