---
id: pr-flash-attention-2202
repo: Dao-AILab/flash-attention
pr: 2202
title: BWD sm100 2cta
author: tzadouri
date: '2026-02-20'
url: https://github.com/Dao-AILab/flash-attention/pull/2202
source_category: upstream-code
architectures:
- sm100
tags:
- cutlass
techniques: []
hardware_features:
- blackwell
kernel_types:
- attention
languages:
- cute-dsl
captured_at: '2026-05-16'
status: merged
merge_sha: 710d3cc239eb5171e8b87bcde9e51349d4affe8b
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- flash_attn/cute/blackwell_helpers.py
- flash_attn/cute/copy_utils.py
- flash_attn/cute/flash_bwd_postprocess.py
- flash_attn/cute/flash_bwd_sm100.py
- flash_attn/cute/mask.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-2202
head_ref_oid: 4641e269ee88638de0e6d57feda0998d9af08836
---
# BWD sm100 2cta

- Repository: `Dao-AILab/flash-attention`
- PR: [2202](https://github.com/Dao-AILab/flash-attention/pull/2202)
- Decision: `Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.`
- Reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.

## Changed Paths

- `flash_attn/cute/blackwell_helpers.py`
- `flash_attn/cute/copy_utils.py`
- `flash_attn/cute/flash_bwd_postprocess.py`
- `flash_attn/cute/flash_bwd_sm100.py`
- `flash_attn/cute/mask.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-2202`
