CUDA: fix negative KV_max values in FA #15321
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slaren
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Aug 14, 2025
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The conditions for triggering the issue seem to be inconsistent and I misinterpreted the results I got. |
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Looking at the code I noticed that, depending on the inputs, there are scenarios where the values in
KV_maxcould become negative. For this to happen there would need to be 16 consecutive tokens that are completely masked out, and the physical batch size would need to be >= 1024. I'm not sure this is going to fix #15294 or #15112 but it should be fixed either way since it could be causing problems in the future.