forked from unom/punktfunk
WP-D leg 1 (.25 RADV, distinct mode) root causes, both real: 1. Output starvation: the fixed 4-deep ring lost to a stream that keeps max_dpb_frames+1 = 8 pictures pending. Zero-copy fix (user requirement, no copies): one picture pool of required_slots + HOLD_HEADROOM(8) images decoupled from DPB slots — a re-activated slot binds a fresh free image, so a delivered picture is never a decode target; the WP-B pin layer became dead and is deleted. Per-image timeline semaphores carry the AVVkFrame contract: decode signals value+1, the presenter waits and signals back, later decodes wait the image's latest value — layout traffic ordered against reference reads with no copy anywhere. 2. RESULT_STATUS queries HANG RADV's VCN firmware (ring timeout, DEVICE_LOST): queryResultStatusSupport=false on the decode family. Queries are now caps-gated; without them poll/wait degrade to timeline-completion verdicts (FFmpeg parity — and the likely reason upstream never wired nb_queries). The Ally-X-class detection runs where drivers advertise the query; .173 probes NVIDIA/Windows-AMD. Also: slice-only bitstream feeding (the field-proven consumer shape), graveyarded pool retirement keyed by release tokens + generation, decode-current-AU-before-status attribution, take_ready drained, H264-bit gating, teardown short-circuit on disconnected channel. On-glass: 48 AUs green on .25 holding 4 frames like the real client. Gates: fmt clean, container clippy -D warnings zero, 27+121+52 green both platforms.