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WS1 local defect log (do not reopen #145–#151)

In-repo record only. Do not file GitHub issues from this list unless the maintainer asks. Hopper re-runs go through the same repro commands; kernel fixes land as PRs against this log.

rmsnorm-dweight

Resolved on 2026-08-13: adapters accumulate parameter_vjp_contributions_fp32 per logical row, so dweight is bitwise 0 across chunk / N×B=1 on H20.

  • Ops: rms_norm, qk_norm
  • Profiles: cuda_bf16, triton_cuda_bf16
  • Judgment: gradient_invariance

det-gemm-dw

Resolved on 2026-08-13: same logical-row FP32 VJP protocol as RMSNorm. Re-run check_gradient_invariance.py --op det_gemm to confirm on the target GPU.

  • Op: det_gemm
  • Profiles: cuda_bf16, triton_cuda_bf16
  • Judgment: gradient_invariance

cuda-logp-no-backward

Resolved on 2026-08-13: FusedLogpGenericOp now has a row-local FP32 softmax VJP bridge. H20 C4/C8 reports all dlogits invariance errors as 0.

  • Op: logp
  • Profile: cuda_bf16 (C2 status is declared, not missing_required)
  • Judgment: gradient_accuracy / gradient_invariance
  • Symptom: FusedLogpGenericOp calls _C.fused_logp with no torch.autograd.Function; no dlogits.
  • Repro: 
    python scripts/check_gradient_invariance.py --op logp --candidate cuda --backend-profile cuda_bf16

triton-attention-left-pad

Resolved on 2026-08-13: the Triton kernel rebases a contiguous valid KV interval to logical columns before both softmax reduction passes. Backward is the matching Triton VJP (no NativeAttentionOp). H20 C8 execute is green.

Tracked C2 gaps (not new defects)

Triton embedding, lm_head, and plain logp are declared candidates. H20 C8 execute ran them with no fallback.

Hopper-only cells (not defects)

CUDA embedding / lm_head / rope / batch_invariant_logp are declared cuda-sm90. H20 C8 execute (docs/design/ws1-c8-execute.json) ran all four green, including CUDA RoPE C3/C4. On non-Hopper hosts classify-only still marks them pending_hopper.