trying to add a driver program (main.cu)

[chakpongchung]

Amazing work! I am trying to develop further on your project.

Is there any reason why the global kernel cannot be called from a main.cu file?

terminate called after throwing an instance of 'c10::Error'
  what():  PyTorch is not linked with support for cuda devices
Exception raised from getDeviceGuardImpl at /croot/pytorch-select_1725478810240/work/c10/core/impl/DeviceGuardImplInterface.h:328 (most recent call first):
frame #0: c10::Error::Error(c10::SourceLocation, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> >) + 0xaa (0x7234bff9e40a in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libc10.so)
frame #1: c10::detail::torchCheckFail(char const*, char const*, unsigned int, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) + 0xf3 (0x7234bff49cb9 in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libc10.so)
frame #2: <unknown function> + 0x10f4314 (0x7234c10f4314 in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libtorch_cpu.so)
frame #3: at::native::to(at::Tensor const&, std::optional<c10::ScalarType>, std::optional<c10::Layout>, std::optional<c10::Device>, std::optional<bool>, bool, bool, std::optional<c10::MemoryFormat>) + 0x13a (0x7234c17972aa in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libtorch_cpu.so)
frame #4: <unknown function> + 0x26e7fbd (0x7234c26e7fbd in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libtorch_cpu.so)
frame #5: at::_ops::to_dtype_layout::call(at::Tensor const&, std::optional<c10::ScalarType>, std::optional<c10::Layout>, std::optional<c10::Device>, std::optional<bool>, bool, bool, std::optional<c10::MemoryFormat>) + 0x209 (0x7234c1e82eb9 in /home/cpchung/miniconda3/lib/python3.10/site-packages/torch/lib/libtorch_cpu.so)
frame #6: at::Tensor::to(c10::TensorOptions, bool, bool, std::optional<c10::MemoryFormat>) const + 0xf7 (0x7234c8699fad in /home/cpchung/dev/experiment/flash-attention-minimal/cmake-build-debug/flash_attention/libai_support.so)
frame #7: forward(at::Tensor, at::Tensor, at::Tensor) + 0x300 (0x7234c8696a56 in /home/cpchung/dev/experiment/flash-attention-minimal/cmake-build-debug/flash_attention/libai_support.so)
frame #8: <unknown function> + 0x27215 (0x574fb9cc9215 in /home/cpchung/dev/experiment/flash-attention-minimal/cmake-build-debug/flash_attention/example-app)
frame #9: <unknown function> + 0x2a1ca (0x7234bfa2a1ca in /lib/x86_64-linux-gnu/libc.so.6)
frame #10: __libc_start_main + 0x8b (0x7234bfa2a28b in /lib/x86_64-linux-gnu/libc.so.6)
frame #11: <unknown function> + 0x26e85 (0x574fb9cc8e85 in /home/cpchung/dev/experiment/flash-attention-minimal/cmake-build-debug/flash_attention/example-app)

I created the the following repo to reproduce the problem.

https://github.com/chakpongchung/debugging