[Bugfix] Add Flash Attention guards in MLACommonImpl constructor #25385
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Signed-off-by: Konrad Zawora <[email protected]>
kzawora-intel
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This pull request aims to fix a NameError that occurs in the MLACommonImpl constructor when vllm_flash_attn is not available. The proposed change from else to elif is_vllm_fa correctly addresses this issue for some platforms. However, my review identifies a critical issue where this change inadvertently breaks FlashAttention support for ROCm platforms. I've provided a suggestion to correct the condition to ensure it works across all intended platforms by checking for the availability of the flash_attn_varlen_func function directly.
Co-authored-by: gemini-code-assist[bot] <176961590+gemini-code-assist[bot]@users.noreply.github.com> Signed-off-by: Konrad Zawora <[email protected]>
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This PR adds a guard preventing non-FlashAttention backends from crashing when inheriting from
MLACommonImpl- in such scenarios,flash_attn_varlen_funcis undefined and construction will fail onNameError: name 'flash_attn_varlen_func' is not defined, which wasn't the case in V0MLACommonImpl.