[CuTe,Bwd] guard softcap for varlen backward#2544
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drisspg merged 1 commit intoMay 7, 2026
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Softcap is currently not supported in varlen backward, but is not properly guarded. This is a band-aid fix until score_mod is supported with varlen in backward.
For example,
pytest tests/cute/test_flash_attn.py::test_flash_attn_varlen_output -k "True-True-True-False-random-128-217-128-False-True-0-15.0"(here15.0is the softcap) fails validation due to incorrectdQ.cc: @drisspg