User runs kwin-fourier with active patch
0001-transaction-bypass-watchDmaBuf-fence-wait.patch — this bypasses
KWin's implicit-sync fence wait on dmabufs. If KWin samples a hantro
CAPTURE buffer before the decoder fence signals, it gets all-zeros
NV12 which renders solid green in YUV→RGB. This is the most likely
cause and is decisively testable via a stock-kwin A/B (item 1).
Hypothesis: pre-iter5 the libva path was masked because vaSyncSurface
provided ordering. iter6/7 may have changed that. Both libva and
ffmpeg-v4l2request paths now expose the lack of fence-wait.
Run-history breadcrumb (#51 introduce, #58 switch to 0002, #59 revert
to 0001) recorded in the findings doc.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
Focused triage of marfrit/libva-multiplanar#1 — dmabuf-wayland green
on ohm independent of decoder backend. Locked question: identify the
layer responsible (libva / ffmpeg / KWin / Mesa-panfrost / kernel)
and file upstream where appropriate. Performance is explicitly out of
scope — user has working slow path via vo=gpu hwdec=v4l2request.
Phase 0 deliverables: vaExportSurfaceHandle + AVDRMFrameDescriptor
modifier captures, Wayland linux-dmabuf-v1 advertise snapshot, pacman
upgrade timeline review for the iter5→iter8 regression window, and
stock-kwin A/B isolating kwin-fourier as a candidate.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>