---
id: pr-vllm-23297
repo: vllm-project/vllm
pr: 23297
title: '[Attention] Allow V1 flash_attn to support cross-attention'
author: russellb
date: '2025-08-22'
url: https://github.com/vllm-project/vllm/pull/23297
source_category: upstream-code
architectures:
- sm100
tags:
- attention
techniques: []
hardware_features: []
kernel_types:
- attention
languages:
- python
captured_at: '2026-04-27'
status: merged
merge_sha: 281710ef9a2a795d57bce997d89a3ed69287464e
inclusion_reason: kernel file changes
changed_paths:
- vllm/v1/attention/backends/flash_attn.py
head_ref_oid: da6a29e6fb4e7a521e1b72c42fe80acd97f5b764
artifact_dir: evidence/pull-bundles/vllm/gh-23297
---
# [Attention] Allow V1 flash_attn to support cross-attention

- Repository: `vllm-project/vllm`
- PR: [23297](https://github.com/vllm-project/vllm/pull/23297)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `vllm/v1/attention/backends/flash_attn.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-23297`
