Boltzmann built linux-fresnel-fourier 7.0-2 in ~50 min (8-core native,
no distcc). Package sha 843fd4462a09b3d9... Deployed to fresnel:
sudo pacman -U clean. extlinux hook updated entry. sddm autologin as
mfritsche persisted. Reboot succeeded; fresnel up on new kernel
within 30s.
5-codec sweep post-reboot: all 5 hashes BYTE-IDENTICAL to pre-iter12
anchors. RFC v2's dma_resv fence machinery does NOT engage libva's
cached-mmap pixel readback path. Consistent with what
reference_dmabuf_resv_blocker.md memo always said: vaDeriveImage /
cached-mmap is the broken path; RFC v2 helps DRM_PRIME / compositor
paths.
Substrate state moved forward (kernel 7.0-1 -> 7.0-2 with RFC v2).
Memory entries updated:
reference_fresnel_kernel_substrate.md (pkg version + patch list)
feedback_rfc_v2_vb2_dma_resv_scope.md (NEW — scope clarification)
iter13 candidates ranked:
α-17: DMA_BUF_IOCTL_SYNC(START|END) in libva backend around image
read sites (~30 LOC).
α-18: switch libva image export to DRM_PRIME (larger refactor).
α-16: OUTPUT byte dump (deferred again).
α-17 is the natural follow-on — Figa's 2024 "userspace responsibility
for explicit sync" line directly addresses the libva-cached-mmap path.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
