From d0e45585391e3ed29894bf0f8300ded8581e4aeb Mon Sep 17 00:00:00 2001 From: Yuan Tang Date: Sat, 8 Feb 2025 22:38:27 -0500 Subject: [PATCH 1/2] [Bugfix][Platform] Check whether selected backend is None in get_attn_backend_cls() Signed-off-by: Yuan Tang --- vllm/platforms/cpu.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/vllm/platforms/cpu.py b/vllm/platforms/cpu.py index 4e0683b8a2de..0abe9b70243b 100644 --- a/vllm/platforms/cpu.py +++ b/vllm/platforms/cpu.py @@ -35,7 +35,7 @@ def get_attn_backend_cls(cls, selected_backend: _Backend, head_size: int, dtype: torch.dtype, kv_cache_dtype: Optional[str], block_size: int, use_v1: bool, use_mla: bool) -> str: - if selected_backend != _Backend.TORCH_SDPA: + if selected_backend is not None and selected_backend != _Backend.TORCH_SDPA: logger.info("Cannot use %s backend on CPU.", selected_backend) logger.info("Using Torch SDPA backend.") return "vllm.attention.backends.torch_sdpa.TorchSDPABackend" From 8085bdde6eb7610f17b1f8894e7ebf05b91f4320 Mon Sep 17 00:00:00 2001 From: Yuan Tang Date: Sat, 8 Feb 2025 23:14:29 -0500 Subject: [PATCH 2/2] Fix pre-commit check Signed-off-by: Yuan Tang --- vllm/platforms/cpu.py | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/vllm/platforms/cpu.py b/vllm/platforms/cpu.py index 0abe9b70243b..179ee6a7d247 100644 --- a/vllm/platforms/cpu.py +++ b/vllm/platforms/cpu.py @@ -35,7 +35,7 @@ def get_attn_backend_cls(cls, selected_backend: _Backend, head_size: int, dtype: torch.dtype, kv_cache_dtype: Optional[str], block_size: int, use_v1: bool, use_mla: bool) -> str: - if selected_backend is not None and selected_backend != _Backend.TORCH_SDPA: + if selected_backend and selected_backend != _Backend.TORCH_SDPA: logger.info("Cannot use %s backend on CPU.", selected_backend) logger.info("Using Torch SDPA backend.") return "vllm.attention.backends.torch_sdpa.TorchSDPABackend"