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Fix FA2 fallback for Blackwell V1 #19781

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Merged
merged 1 commit into from
Jun 19, 2025
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Fix FA2 fallback for Blackwell V1 #19781

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2 changes: 1 addition & 1 deletion vllm/platforms/cuda.py
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Original file line number Diff line number Diff line change
Expand Up @@ -255,7 +255,7 @@ def get_attn_backend_cls(cls, selected_backend, head_size, dtype,
"install FlashInfer for better performance.")
pass
# FlashAttention is the default for SM 8.0+ GPUs
elif cls.has_device_capability(80):
if cls.has_device_capability(80):
logger.info_once("Using Flash Attention backend on V1 engine.")
return ("vllm.v1.attention.backends."
"flash_attn.FlashAttentionBackend")
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