Commit Graph

3 Commits

Author SHA1 Message Date
enricobuehler 1d17524151 feat(host): isolate the zero-copy GPU import in a worker process
The tiled EGL/GL→CUDA import crashed the whole host (SIGSEGV inside
libnvidia-eglcore via cuGraphicsMapResources) when the compositor
invalidated an imported dmabuf mid-map — reproduced on the Bazzite F44
Game→Desktop switch (design/zerocopy-hardening-handoff.md). A driver
SIGSEGV is uncatchable in-process, so the whole EglImporter (tiled
EGL/GL→CUDA and LINEAR Vulkan→CUDA) now runs in a per-capture
`zerocopy-worker` subprocess: dmabuf fds go over a SEQPACKET socketpair
(SCM_RIGHTS, sent once per buffer keyed by dmabuf st_ino; NeedFd resend
self-heals cache desync), frames come back as CUDA-IPC pooled device
buffers (still zero-copy, +one socket RTT/frame). Worker death poisons
the capturer so the existing capture-loss rebuild runs — the host
survives; 3 consecutive deaths latch the GPU import off (CPU/SHM path).
PUNKTFUNK_ZEROCOPY_INPROC=1 keeps the old in-process import for
debugging/A-B.

Also fixed along the way: a failed *tiled* import no longer falls
through to the CPU mmap de-pad (which scrambled tiled bytes; LINEAR
keeps the fallback); Nv12Blit dropped its GL textures while still
CUDA-registered (unregister now runs first); GlBlit had no Drop at all
(GL objects leaked per size change); VkBridge's per-fd src cache is now
invalidated on renegotiation/eviction instead of never.

Design: design/zerocopy-worker-isolation.md. Unit tests: 14 new
(protocol fd-passing, worker dispatch, client handshake/death/NeedFd,
death latch). On-glass validated on the RTX 5070 Ti/GNOME box (.21):
the worker path streams at p50 1.30 ms (NV12, 1800 frames 0-mismatched,
parity with the in-process path), and a kill -9 of the worker
mid-stream is survived by the host and recovered — poison -> capture
lost, rebuilding pipeline in place -> a fresh worker in ~185 ms ->
streaming resumes (2385 frames, 0 mismatched). A real KWin
compositor-crash repro is still pending (a worker kill -9 is strictly
harsher, so it corroborates).

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
2026-07-06 10:33:43 +00:00
enricobuehler b54695739d docs(host): prove every unsafe block in the Linux FFI files + gate them (unsafe-proof program 2/N)
Continues the structural unsafe-proof program (every unsafe carries a documented
proof of soundness; the file gains #![deny(clippy::undocumented_unsafe_blocks)]
so it stays proven). This batch covers all 10 remaining pure-Linux files
(104 blocks), each proof stating the REAL invariant — not boilerplate:

  zerocopy/cuda.rs (26)   leaked process-lifetime libcuda fn-ptr table; opaque
                          CUcontext never dereferenced; free-exactly-once via the
                          Arc<Mutex<PoolInner>> ownership graph; dmabuf fd take/close split
  zerocopy/egl.rs (18)    eglGetProcAddress'd procs with the GL context current;
                          EGLImage liveness; the two-call modifier-query bounds
  zerocopy/vulkan.rs (4)  copy-bounds arithmetic (src_size>=span); Send = thread
                          confinement to the punktfunk-pipewire thread
  dmabuf_fence.rs (4)     poll/ioctl/close fd liveness + ownership
  capture/linux/mod.rs (16)  spa_data repr(transparent) cast; null-checked spa
                          derefs; single-loop-thread buffer ownership until requeue
  inject/linux/gamepad.rs (10)  uinput ioctl request-number ↔ struct-size match
                          (static-asserted); InputEventRaw no-padding for the byte cast
  encode/linux/vaapi.rs (15) + encode/linux/mod.rs (9)  ffmpeg object ownership/
                          free ladders; VAAPI/DRM graph; Send = single-thread transfer
  inject/linux/wlr.rs (2), vdisplay/linux/kwin.rs (1)

No memory-unsafety SUSPECT blocks were found — the unsafe is sound. The vaapi
agent did flag two real AVBufferRef *leaks* (not UB) in DmabufInner::open; marked
inline with NOTE(leak) and addressed in a follow-up.

Verified: cargo clippy -p punktfunk-host --all-targets -- -D warnings is clean
(each file's deny gate hard-errors on any undocumented block).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-26 09:00:30 +00:00
enricobuehler fced221684 refactor(windows-host): confine platform code under windows/ + linux/ folders (Goal-1 stage 6)
Move 36 platform-specific files into per-module `windows/` and `linux/` subfolders (and the
shared HID codecs into `inject/proto/`):
  capture/{windows,linux}/  encode/{windows,linux}/  inject/{windows,linux,proto}/
  audio/{windows,linux}/  vdisplay/{windows,linux}/
  src/windows/ (service, wgc_helper, win_adapter, win_display)
  src/linux/  (dmabuf_fence, drm_sync, zerocopy/)

Done with `#[path]`, NOT a module rename: every file moves into its folder while the
`crate::*::*` module names stay FLAT, so all caller paths and every internal `super::`/`crate::`
reference are unchanged — only the parent `mod` decls gained `#[path = "..."]`. This is the
codebase's existing pattern (inject's gamepad_windows) and makes the move byte-identical in
behaviour with ZERO reference churn, far lower risk than collapsing to a single
`crate::capture::windows::` namespace (that deeper rename is an optional follow-on; this delivers
the cfg-sprawl folder confinement the stage is about). Done LAST, after the semantic stages, so
the path churn didn't fight them.

Verified: Linux cargo check + clippy (-D warnings) clean; my mod-decl changes fmt-clean (the 3
remaining fmt diffs are pre-existing local-rustfmt-version skew that moved with their files); all
36 `#[path]` targets exist; no internal `#[path]`/`include!`/file-child-mod in any moved file
(the inline `mod X {` blocks are self-contained). Box build to follow.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
2026-06-25 18:53:45 +00:00