Error while Installing modules for GKD example.

[jeff4700]

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Question Description / 问题描述

Flash Attention Installation Error

git clone https://github.com/modelscope/ms-swift.git
cd ms-swift
uv venv --python python3.12
source .venv/bin/activate
uv pip install -e .
uv pip install flash-attn --no-build-isolation

bash ms-swift/examples/train/rlhf/gkd/think_model.sh

Error:
ImportError: .../flash_attn_2_cuda.cpython-312-x86_64-linux-gnu.so: undefined symbol: _ZN3c104cuda29c10_cuda_check_implementationEiPKcS2_ib

---

nvidia-smi

Mon Mar  9 20:51:33 2026       
+-----------------------------------------------------------------------------------------+
| NVIDIA-SMI 575.64.03              Driver Version: 575.64.03      CUDA Version: 12.9   

nvcc --version

nvcc: NVIDIA (R) Cuda compiler driver
Copyright (c) 2005-2025 NVIDIA Corporation
Built on Tue_May_27_02:21:03_PDT_2025
Cuda compilation tools, release 12.9, V12.9.86
Build cuda_12.9.r12.9/compiler.36037853_0

python -c "import torch; print(torch.version, torch.version.cuda)"
2.10.0+cu128 12.8

What I did:

Reinstalled Cuda toolkit

sudo apt update
sudo apt install -y cuda-toolkit-12-9

sudo ln -sfn /usr/local/cuda-12.9 /usr/local/cuda

Reinstalled pytorch for 12.9

uv pip uninstall torch torchvision torchaudio
uv pip install torch torchvision torchaudio \
  --index-url https://download.pytorch.org/whl/cu129
uv pip install ninja packaging wheel

Then when I run this command, it never proceed for 30 mins.
uv pip install flash-attn --no-build-isolation --no-cache

What should I do?

[hjh0119]

plz refer to flash attention issue https://github.com/Dao-AILab/flash-attention/issues