---
id: pr-vllm-32974
repo: vllm-project/vllm
pr: 32974
title: '[Attention] FA4 integration'
author: LucasWilkinson
date: '2026-03-01'
url: https://github.com/vllm-project/vllm/pull/32974
source_category: upstream-code
architectures:
- sm100
tags:
- attention
- mla
techniques: []
hardware_features: []
kernel_types:
- attention
- mla
languages:
- cuda-cpp
captured_at: '2026-04-27'
status: merged
merge_sha: 8b5014d3dd343736ccf3e26cd44a0bb7700d205c
inclusion_reason: kernel file changes
changed_paths:
- .buildkite/test_areas/misc.yaml
- .gitignore
- cmake/external_projects/vllm_flash_attn.cmake
- docs/design/attention_backends.md
- requirements/cuda.txt
- setup.py
- tools/pre_commit/generate_attention_backend_docs.py
- vllm/config/attention.py
- vllm/model_executor/layers/attention/mla_attention.py
- vllm/model_executor/layers/attention/mm_encoder_attention.py
- vllm/v1/attention/backends/fa_utils.py
- vllm/v1/attention/backends/flash_attn.py
- vllm/v1/cudagraph_dispatcher.py
- vllm/vllm_flash_attn/__init__.py
- vllm/vllm_flash_attn/flash_attn_interface.py
head_ref_oid: 14cface5a4cd1d6a17459f8981429e680fc8c185
artifact_dir: evidence/pull-bundles/vllm/gh-32974
---
# [Attention] FA4 integration

- Repository: `vllm-project/vllm`
- PR: [32974](https://github.com/vllm-project/vllm/pull/32974)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `.buildkite/test_areas/misc.yaml`
- `.gitignore`
- `cmake/external_projects/vllm_flash_attn.cmake`
- `docs/design/attention_backends.md`
- `requirements/cuda.txt`
- `setup.py`
- `tools/pre_commit/generate_attention_backend_docs.py`
- `vllm/config/attention.py`
- `vllm/model_executor/layers/attention/mla_attention.py`
- `vllm/model_executor/layers/attention/mm_encoder_attention.py`
- `vllm/v1/attention/backends/fa_utils.py`
- `vllm/v1/attention/backends/flash_attn.py`
- `vllm/v1/cudagraph_dispatcher.py`
- `vllm/vllm_flash_attn/__init__.py`
- `vllm/vllm_flash_attn/flash_attn_interface.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-32974`
