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>> +} > > Any particular reason why using negation instead of a ARM64_HAS_FPSIMD? > A potential problem would be the default cpus_have_const_cap() > implementation and the default static key having a slight performance > impact. The negation was chosen to avoid hotpatching in the most common case. But as you said, it has an impact on the other side. I think doing a one time hotpatching at boot time is more optimal than penalising a bunch of other users throughout the execution. I will take a look at changing it back to a ARM64_HAS_FPSIMD. >> }, >> + { >> + /* FP/SIMD is not implemented */ >> + .capability = ARM64_HAS_NO_FPSIMD, >> + .def_scope = SCOPE_SYSTEM, >> + .min_field_value = 0, >> + .matches = has_no_fpsimd, >> + }, > > If we go for negation, I don't think we need a min_field_value at all, > the matching is done by the has_no_fpsimd() function. You're right. Suzuki