{
  "finding_id": "DF-5170",
  "title": "evergreen_copy_dma discards radeon_sync_resv()/radeon_sync_rings() returns — Evergreen/Cayman twin of DF-4871/DF-5089: DMA copy committed without cross-ring ordering on sync failure, silent bo data corruption",
  "verdict": "untested",
  "impact": "none",
  "reproduce": {
    "build": "n/a — no userland PoC; hardware-gated (requires Evergreen/Cayman GPU bound to radeon DRM)",
    "run": "dfbsd-qemu/vm.sh run_root 'pciconf -l | grep -i vga; kldstat | grep -ci \"radeon\\|drm\"; ls /dev/dri'  # documents the hardware gate (run.log/env.txt)",
    "expected": "Guest: QEMU std-VGA chip=0x11111234, 0 drm modules, no /dev/dri — evergreen_copy_dma unreachable at runtime; source-level proof in VERDICT.md"
  },
  "kernel_refs": [
    "sys/dev/drm/radeon/evergreen_dma.c:130",
    "sys/dev/drm/radeon/evergreen_dma.c:131",
    "sys/dev/drm/radeon/evergreen_dma.c:154",
    "sys/dev/drm/radeon/radeon_sync.c:106",
    "sys/dev/drm/radeon/radeon_sync.c:153",
    "sys/dev/drm/radeon/radeon_sync.c:165",
    "sys/dev/drm/radeon/radeon_ib.c:135",
    "sys/dev/drm/radeon/radeon_ib.c:149",
    "sys/dev/drm/radeon/radeon.h:628",
    "sys/dev/drm/radeon/radeon.h:2708",
    "sys/dev/drm/radeon/evergreend.h:1416",
    "sys/dev/drm/radeon/radeon_asic.c:1373"
  ],
  "artifacts": [
    "README.md",
    "VERDICT.md",
    "fix.diff",
    "env.txt",
    "run.log",
    "manifest.json",
    "verdict.json"
  ],
  "known_not_refiled": ["DF-2167 (size computation overflow, evergreen_dma.c:121)"]
}