forked from unom/punktfunk
WP4.5's device-selection half, closed as the observability intermediate after TWO selection designs died in adversarial review: - Attempt #1 (d26bcf05, withdrawn): match pf_gpu::selected_gpu(). Its Linux auto arm answers "the NVIDIA GPU" whenever /dev/nvidiactl exists, moving the encoder off the iGPU that can import the compositor's dmabufs on an Intel-compositor + NVIDIA-present laptop — import failures feed the process-wide raw-dmabuf latch, which never un-latches. - Attempt #2 (this session, withdrawn before commit): anchor on the PUNKTFUNK_RENDER_NODE-else-renderD128 node via VK_EXT_physical_device_drm. Render minors are driver-BIND-ORDER artifacts, not display topology: on the common AMD-iGPU + NVIDIA-display desktop, in-tree amdgpu binds before out-of-tree nvidia, so the anchor deterministically picks the idle iGPU while the compositor allocates on NVIDIA — the same latch, opposite polarity, behind a success-looking log. The correct oracle is evidence of which device ALLOCATED the capture buffers — producer identity from the capture negotiation, threaded per session into this open. Until that plumbing exists, selection stays first-usable, both call sites still share one selector (pure over the device list, so capture_modifiers and open_inner cannot diverge — including across an in-place resize's re-open, which does not renegotiate capture), and the open logs ONE greppable line: picked vendor/device, the anchor node and its owner (DRM render major/minor, VK_EXT_pci_bus_info fallback), and the console's selected GPU. A wrong-device session on a multi-GPU host used to be completely invisible; a field report can now show it. No WARN arm on purpose: the wrong-pick direction inverts between the laptop and desktop topologies, so a mismatch is not evidence of a wrong pick, and a warning that fires forever on healthy hosts teaches people to ignore warnings. Decision recorded against the audit's framing: manual console GPU selection stays unhonored by pyrowave on Linux (the Windows twin honors it) — honoring console-mutable state without per-session threading is what made attempt #1 unsafe. Verified on the 780M: the line resolves all three identities (1002:15bf x3, DRM-props match live); full pyrowave on-glass suite green; selection behaviour byte-for-byte unchanged. WP4.5 (device half). Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>