3 Commits

Author	SHA1	Message	Date
enricobuehler	986402f731	fix(inject,zerocopy,capture): teardown deadlock, GL→CUDA copy race, cursor-meta OOB read ... The three high-severity defects from the round-1 sweep of pf-inject / pf-zerocopy / pf-capture (adjudicated against source — all 7 reported criticals in these crates downgraded; these were the real highs). - pf-inject steam_gadget: `SteamDeckGadget::drop` set `running=false` then joined the control thread, which spends steady state parked in a blocking, no-timeout `EVENT_FETCH` ioctl that only tests `running` at its loop top. The flag never reaches it, closing the fd can't wake an in-flight ioctl (the syscall holds a file reference, and the fd is shared via Arc by the very threads being joined), so the join hung — and it runs on the session input thread via `PadSlots::sweep`, driven by the client's `active_mask`, so a remote peer clearing its pad bit could freeze all session input. Now wakes the parked threads with SIGUSR1 (no-op, non-SA_RESTART handler → the ioctl returns EINTR and the loop exits), retried until each reports done and bounded (~1s). - pf-zerocopy cuda: the GL→CUDA "sync point" was never established for the copy. `cuGraphicsMapResources`/`UnmapResources` were issued on the NULL stream, but the D2D copy runs on `copy_stream()`, a `CU_STREAM_NON_BLOCKING` stream exempt from implicit NULL-stream ordering — and the GL de-tile/CSC that produced the texture ends with only `glFlush` (no fence). So the copy could race ahead of the not-yet-retired GL draw: intermittent stale/torn frames under GPU load, on the default NVIDIA capture→encode path. Map, copy, and unmap now share `copy_stream()`, so map's device-side guarantee orders the GL work before the copy. Zero-copy preserved (no GPU→CPU→GPU roundtrip). - pf-capture cursor meta: `update_cursor_meta` trusted three producer-written fields (bitmap_offset, pixel offset, stride) with no bound against the metadata region, driving OOB pointer arithmetic and an oversized `from_raw_parts` — an OOB read that SIGSEGVs inside the PipeWire `.process` callback (uncatchable by the surrounding `catch_unwind`). Switched to `spa_buffer_find_meta` to obtain the region's real `size` and validate every offset with checked arithmetic before each deref/slice, mirroring the fd-length guard the main frame path already applies. Compile + existing tests green on Linux .21 (real RTX 5070 Ti): pf-inject 74/0, pf-zerocopy 17/0, pf-capture 1/0. The gadget deadlock path only executes on a SteamOS host with raw_gadget/dummy_hcd (not reproducible on the CachyOS box), so that fix is reasoned + compile-verified, not runtime-exercised. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>	2026-07-19 22:53:15 +02:00
enricobuehler	5e1e64e50b	perf(latency): T2.5b — NV12 compute CSC on the LINEAR/gamescope zero-copy path ... design/latency-reduction-2026-07.md T2.5's Linux half: the LINEAR dmabuf path (gamescope's only offer) fed NVENC RGB, paying its internal RGB->YUV CSC on the SM the game is saturating — the exact contention §5.A removed everywhere else. The Vulkan bridge now carries a buffer-to-buffer RGB->NV12 compute shader (rgb2nv12_buf.comp, BT.709 limited, coefficient-identical to pf-encode's rgb2yuv.comp; whole-word writes so no 8-bit-storage feature is needed): import dmabuf -> dispatch CSC into the exportable buffer -> CUDA de-strides both planes into a pooled two-plane NV12 buffer. PUNKTFUNK_NV12 (default-on) now covers LINEAR; a CSC failure latches RGB for the stream (mid-frame fallback, no dropped frame); 4:4:4 LINEAR sessions stay RGB (never silently subsample). New ImportKind::LinearNv12 rides the existing worker IPC (appended last per the wire-tag rule); cursor stays downstream (blend_nv12). Validated: .21 clippy -D warnings (pf-zerocopy/pf-capture/host+nvenc) + 17 zero-copy tests. Owed: on-glass gamescope session (visual + dmon sm% check). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>	2026-07-17 20:14:20 +02:00
enricobuehler	85bc5b9a3f	refactor(host/W6.2): extract the Linux zero-copy GPU plumbing into the pf-zerocopy leaf crate ... linux/zerocopy/* (CUDA context/buffers + EGL/Vulkan dmabuf import + the isolated import worker) and linux/dmabuf_fence.rs move wholesale into crates/pf-zerocopy, so the coming pf-frame vocabulary crate (FramePayload::Cuda owns a DeviceBuffer) and the pf-encode/pf-capture subsystem crates can reach the GPU plumbing without the host orchestrator in between (plan §W6). Content stays Linux-only; the crate compiles to an empty lib elsewhere, so dependents carry a plain dependency. drm_fourcc deliberately does NOT move: it consumes the frame vocabulary (PixelFormat), which sits ABOVE pf-zerocopy — it lives with capture for now and moves into pf-frame next. cuda's ffi re-export bumps pub(crate)->pub (the raw CUdeviceptr vocabulary is consumed across the crate boundary by the encode backends). A crate::zerocopy shim module keeps every existing path valid until capture/encode themselves move out. Verified: Linux clippy -D warnings (pf-zerocopy --all-targets + host nvenc,vulkan-encode,pyrowave --all-targets) + 17/17 pf-zerocopy tests + 321/321 host tests; Windows clippy nvenc,amf-qsv --all-targets Finished exit 0. Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>	2026-07-17 09:41:15 +02:00