---
id: pr-vllm-18807
repo: vllm-project/vllm
pr: 18807
title: '[BugFix] FA2 MLA Accuracy Issue'
author: LucasWilkinson
date: '2025-05-28'
url: https://github.com/vllm-project/vllm/pull/18807
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: ce75efeecb57acb5421aeb545a95e922f3dc8b3e
inclusion_reason: kernel file changes
changed_paths:
- csrc/attention/merge_attn_states.cu
- vllm/attention/backends/mla/common.py
- vllm/v1/attention/backends/mla/common.py
head_ref_oid: 3df596e125efaeb07d68f3e3c78c27cdf84960a8
artifact_dir: evidence/pull-bundles/vllm/gh-18807
---
# [BugFix] FA2 MLA Accuracy Issue

- Repository: `vllm-project/vllm`
- PR: [18807](https://github.com/vllm-project/vllm/pull/18807)
- Decision: `kernel file changes`
- Reason: kernel file changes

## Changed Paths

- `csrc/attention/merge_attn_states.cu`
- `vllm/attention/backends/mla/common.py`
- `vllm/v1/attention/backends/mla/common.py`

## Evidence Bundle

`evidence/pull-bundles/vllm/gh-18807`
