---
id: pr-flash-attention-2070
repo: Dao-AILab/flash-attention
pr: 2070
title: 'Add score-mod bwd support '
author: drisspg
date: '2025-12-16'
url: https://github.com/Dao-AILab/flash-attention/pull/2070
source_category: upstream-code
architectures:
- sm100
- sm90
tags:
- arch_pipeline
- attention_kv
- benchmark_test
- block sparse
- compiler_runtime
- hopper
techniques:
- async-copy
- pipeline-stages
hardware_features:
- blackwell
- hopper
- tma
- tmem
kernel_types:
- attention
- compiler
- runtime
- softmax
languages:
- cute-dsl
captured_at: '2026-05-16'
status: merged
merge_sha: ac9b5f107f2f19cd0ca6e01548d20d072a46335c
inclusion_reason: 'Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.'
changed_paths:
- flash_attn/cute/flash_bwd_sm100.py
- flash_attn/cute/interface.py
- flash_attn/cute/softmax.py
- tests/cute/test_score_mod.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-2070
head_ref_oid: 94a7c499629091a4a46328078a4e1c75ebb3b02c
---
# Add score-mod bwd support 

- Repository: `Dao-AILab/flash-attention`
- PR: [2070](https://github.com/Dao-AILab/flash-attention/pull/2070)
- Decision: `Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.`
- Reason: Extract the architecture assumption first: SM target, TMA/WGMMA/tcgen path, cluster use, and pipeline stages.

## Changed Paths

- `flash_attn/cute/flash_bwd_sm100.py`
- `flash_attn/cute/interface.py`
- `flash_attn/cute/softmax.py`
- `tests/cute/test_score_mod.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-2070`
