---
id: pr-vllm-23465
repo: vllm-project/vllm
pr: 23465
title: '[Attention][FA3] Update FA3 to include new swizzle optimization'
author: LucasWilkinson
date: '2026-02-03'
url: https://github.com/vllm-project/vllm/pull/23465
source_category: upstream-code
architectures:
- sm100
tags:
- attention
- mla
- swizzling
techniques:
- swizzling
hardware_features: []
kernel_types:
- attention
- mla
languages:
- python
captured_at: '2026-04-27'
status: merged
merge_sha: 2267cb1cfd838a192f47ff677d91164fb5cb2862
inclusion_reason: kernel file changes
changed_paths:
- cmake/external_projects/vllm_flash_attn.cmake
- vllm/v1/attention/backends/flash_attn.py
- vllm/v1/attention/backends/mla/flashattn_mla.py
head_ref_oid: 3459c9ff6a37ea83f2123f26c5b50cddad54940f
artifact_dir: evidence/pull-bundles/vllm/gh-23465
---
# [Attention][FA3] Update FA3 to include new swizzle optimization

- Repository: `vllm-project/vllm`
- PR: [23465](https://github.com/vllm-project/vllm/pull/23465)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `cmake/external_projects/vllm_flash_attn.cmake`
- `vllm/v1/attention/backends/flash_attn.py`
- `vllm/v1/attention/backends/mla/flashattn_mla.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-23465`
