---
id: pr-flash-attention-2400
repo: Dao-AILab/flash-attention
pr: 2400
title: '[AMD ROCm] Update CK and add RDNA 3/4 support'
author: rocking5566
date: '2026-03-26'
url: https://github.com/Dao-AILab/flash-attention/pull/2400
source_category: upstream-code
architectures:
- sm100
tags:
- attention kernel
- benchmark kernel
- cuda kernel
- fmha
- triton kernel
techniques: []
hardware_features: []
kernel_types:
- attention
languages:
- cuda-cpp
- triton
captured_at: '2026-05-16'
status: merged
merge_sha: 5301a359f59ef8fa10f211618d9f7a69716a8898
inclusion_reason: Search-matched CUDA kernel optimization PR; materialize diff/source before synthesis.
changed_paths:
- README.md
- csrc/composable_kernel
- csrc/flash_attn_ck/flash_common.hpp
- csrc/flash_attn_ck/mha_bwd.cpp
- csrc/flash_attn_ck/mha_fwd.cpp
- csrc/flash_attn_ck/mha_fwd_head_grouping_utils.hpp
- csrc/flash_attn_ck/mha_varlen_bwd.cpp
- csrc/flash_attn_ck/mha_varlen_fwd.cpp
- setup.py
- tests/test_flash_attn_ck.py
artifact_dir: evidence/pull-bundles/flash-attention/gh-2400
head_ref_oid: ba957ffb07456e2519456e083b0fa336a002067c
---
# [AMD ROCm] Update CK and add RDNA 3/4 support

- Repository: `Dao-AILab/flash-attention`
- PR: [2400](https://github.com/Dao-AILab/flash-attention/pull/2400)
- 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

- `README.md`
- `csrc/composable_kernel`
- `csrc/flash_attn_ck/flash_common.hpp`
- `csrc/flash_attn_ck/mha_bwd.cpp`
- `csrc/flash_attn_ck/mha_fwd.cpp`
- `csrc/flash_attn_ck/mha_fwd_head_grouping_utils.hpp`
- `csrc/flash_attn_ck/mha_varlen_bwd.cpp`
- `csrc/flash_attn_ck/mha_varlen_fwd.cpp`
- `setup.py`
- `tests/test_flash_attn_ck.py`

## Evidence Bundle

`evidence/pull-bundles/flash-attention/gh-2400`
