flash-attn 安装失败

[91zw]

Solution to issue cannot be found in the documentation.

• I checked the documentation.

Issue

windows10,cuda11.8,torch2.7.1+cu118,torchvision0.22.1+cu118,需要安装哪个版本的flash-attn

Installed packages

accelerate                 1.4.0            pypi_0           pypi
addict                     2.4.0            pypi_0           pypi
aiofiles                   24.1.0           pypi_0           pypi
annotated-doc              0.0.4            pypi_0           pypi
annotated-types            0.7.0            pypi_0           pypi
anyio                      4.12.0           pypi_0           pypi
brotli                     1.2.0            pypi_0           pypi
bzip2                      1.0.8            h2bbff1b_6
ca-certificates            2025.12.2        haa95532_0
certifi                    2025.11.12       pypi_0           pypi
charset-normalizer         3.4.4            pypi_0           pypi
click                      8.3.1            pypi_0           pypi
colorama                   0.4.6            pypi_0           pypi
contourpy                  1.3.2            pypi_0           pypi
cycler                     0.12.1           pypi_0           pypi
decord                     0.6.0            pypi_0           pypi
einops                     0.8.1            pypi_0           pypi
exceptiongroup             1.3.1            pypi_0           pypi
expat                      2.7.3            h885b0b7_4
fastapi                    0.124.0          pypi_0           pypi
ffmpy                      1.0.0            pypi_0           pypi
filelock                   3.20.0           pypi_0           pypi
flash-attn                 2.7.0.post2      pypi_0           pypi
fonttools                  4.61.0           pypi_0           pypi
fsspec                     2025.12.0        pypi_0           pypi
ftfy                       6.3.1            pypi_0           pypi
gradio                     6.0.2            pypi_0           pypi
gradio-client              2.0.1            pypi_0           pypi
groovy                     0.1.2            pypi_0           pypi
h11                        0.16.0           pypi_0           pypi
httpcore                   1.0.9            pypi_0           pypi
httpx                      0.28.1           pypi_0           pypi
huggingface-hub            0.36.0           pypi_0           pypi
idna                       3.11             pypi_0           pypi
imageio                    2.37.2           pypi_0           pypi
iopath                     0.1.10           pypi_0           pypi
jinja2                     3.1.6            pypi_0           pypi
joblib                     1.5.2            pypi_0           pypi
kiwisolver                 1.4.9            pypi_0           pypi
lazy-loader                0.4              pypi_0           pypi
libexpat                   2.7.3            h885b0b7_4
libffi                     3.4.4            hd77b12b_1
libzlib                    1.3.1            h02ab6af_0
markdown-it-py             4.0.0            pypi_0           pypi
markupsafe                 3.0.3            pypi_0           pypi
matplotlib                 3.10.7           pypi_0           pypi
mdurl                      0.1.2            pypi_0           pypi
mmengine                   0.8.2            pypi_0           pypi
mpmath                     1.3.0            pypi_0           pypi
networkx                   3.4.2            pypi_0           pypi
ninja                      1.13.0           pypi_0           pypi
numpy                      2.2.6            pypi_0           pypi
opencv-python              4.12.0.88        pypi_0           pypi
openssl                    3.0.18           h543e019_0
orjson                     3.11.5           pypi_0           pypi
packaging                  25.0             pypi_0           pypi
pandas                     2.3.3            pypi_0           pypi
pillow                     12.0.0           pypi_0           pypi
pip                        25.3             pyhc872135_0
platformdirs               4.5.1            pypi_0           pypi
portalocker                3.2.0            pypi_0           pypi
psutil                     7.1.3            pypi_0           pypi
pycocotools                2.0.11           pypi_0           pypi
pydantic                   2.12.4           pypi_0           pypi
pydantic-core              2.41.5           pypi_0           pypi
pydub                      0.25.1           pypi_0           pypi
pygments                   2.19.2           pypi_0           pypi
pyparsing                  3.2.5            pypi_0           pypi
python                     3.10.19          h981015d_0
python-dateutil            2.9.0.post0      pypi_0           pypi
python-multipart           0.0.20           pypi_0           pypi
pytz                       2025.2           pypi_0           pypi
pywin32                    311              pypi_0           pypi
pyyaml                     6.0.3            pypi_0           pypi
regex                      2025.11.3        pypi_0           pypi
requests                   2.32.5           pypi_0           pypi
rich                       14.2.0           pypi_0           pypi
safehttpx                  0.1.7            pypi_0           pypi
safetensors                0.7.0            pypi_0           pypi
sam3                       0.1.2            pypi_0           pypi
scikit-image               0.25.2           pypi_0           pypi
scikit-learn               1.7.2            pypi_0           pypi
scipy                      1.15.3           pypi_0           pypi
semantic-version           2.10.0           pypi_0           pypi
setuptools                 80.9.0           py310haa95532_0
shellingham                1.5.4            pypi_0           pypi
six                        1.17.0           pypi_0           pypi
sqlite                     3.51.0           hda9a48d_0
starlette                  0.50.0           pypi_0           pypi
sympy                      1.14.0           pypi_0           pypi
termcolor                  3.2.0            pypi_0           pypi
threadpoolctl              3.6.0            pypi_0           pypi
tifffile                   2025.5.10        pypi_0           pypi
timm                       1.0.9            pypi_0           pypi
tk                         8.6.15           hf199647_0
tokenizers                 0.21.4           pypi_0           pypi
tomli                      2.3.0            pypi_0           pypi
tomlkit                    0.13.3           pypi_0           pypi
torch                      2.7.1+cu118      pypi_0           pypi
torchaudio                 2.7.1+cu118      pypi_0           pypi
torchvision                0.22.1+cu118     pypi_0           pypi
tqdm                       4.67.1           pypi_0           pypi
transformers               4.50.1           pypi_0           pypi
typer                      0.20.0           pypi_0           pypi
typing-extensions          4.15.0           pypi_0           pypi
typing-inspection          0.4.2            pypi_0           pypi
tzdata                     2025.2           pypi_0           pypi
ucrt                       10.0.22621.0     haa95532_0
urllib3                    2.6.1            pypi_0           pypi
uvicorn                    0.38.0           pypi_0           pypi
vc                         14.3             h2df5915_10
vc14_runtime               14.44.35208      h4927774_10
vs2015_runtime             14.44.35208      ha6b5a95_10
wcwidth                    0.2.14           pypi_0           pypi
wheel                      0.45.1           py310haa95532_0
xz                         5.6.4            h4754444_1
yapf                       0.43.0           pypi_0           pypi
zlib                       1.3.1            h02ab6af_0

Environment info

active environment : vlm-fo1
    active env location : C:\Users\zw\anaconda3\envs\vlm-fo1
            shell level : 1
       user config file : C:\Users\zw\.condarc
 populated config files : C:\Users\zw\anaconda3\.condarc
                          C:\Users\zw\.condarc
          conda version : 25.5.1
    conda-build version : 25.5.0
         python version : 3.13.5.final.0
                 solver : libmamba (default)
       virtual packages : __archspec=1=skylake
                          __conda=25.5.1=0
                          __cuda=13.1=0
                          __win=10.0.19045=0
       base environment : C:\Users\zw\anaconda3  (writable)
      conda av data dir : C:\Users\zw\anaconda3\etc\conda
  conda av metadata url : None
           channel URLs : https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/pytorch/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/pytorch/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/conda-forge/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/cloud/conda-forge/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/free/noarch
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/win-64
                          https://mirrors.tuna.tsinghua.edu.cn/anaconda/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/main/win-64
                          https://repo.anaconda.com/pkgs/main/noarch
                          https://repo.anaconda.com/pkgs/r/win-64
                          https://repo.anaconda.com/pkgs/r/noarch
                          https://repo.anaconda.com/pkgs/msys2/win-64
                          https://repo.anaconda.com/pkgs/msys2/noarch
          package cache : C:\Users\zw\anaconda3\pkgs
                          C:\Users\zw\.conda\pkgs
                          C:\Users\zw\AppData\Local\conda\conda\pkgs
       envs directories : C:\Users\zw\anaconda3\envs
                          C:\Users\zw\.conda\envs
                          C:\Users\zw\AppData\Local\conda\conda\envs
               platform : win-64
             user-agent : conda/25.5.1 requests/2.32.3 CPython/3.13.5 Windows/10 Windows/10.0.19045 solver/libmamba conda-libmamba-solver/25.4.0 libmambapy/2.0.5 aau/0.7.1 c/. s/. e/.
          administrator : False
             netrc file : None
           offline mode : False

[weiji14]

The conda-forge channel only has flash-attn built for linux-64 and linux-aarch64, not windows. Don't think we can support Windows builds on the GPU CI at the moment, you can check upstream unofficial wheels like Dao-AILab/flash-attention#1820

conda-forge这里只支持linux安装，目前没有Windows的版本。你可以参考以上的链接看能不能安装。

[carterbox]

I can test if we even have the same problem on Windows since we use a different setup.py from upstream. Otherwise, as @weiji14 will have to wait for Dao-AILab/flash-attention#2047 to be resolved.

[carterbox]

I don't think upstream supports Windows for flash attention 2.x. Our build didn't even get to the linking step mentioned in the issues above. It stopped earlier with syntax errors from MSVC, so they must have made other changes in 3.x to fix compatibility with the Windows toolchain.