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Add support for FPU flags for PDs#316

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JDuchniewicz wants to merge 2 commits intoseL4:mainfrom
JDuchniewicz:fpu_flag
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Add support for FPU flags for PDs#316
JDuchniewicz wants to merge 2 commits intoseL4:mainfrom
JDuchniewicz:fpu_flag

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@JDuchniewicz
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@JDuchniewicz JDuchniewicz commented Dec 11, 2025

Allows for PDs to specify the fpu flag to explicitly disable the FPU usage in them. By default it's set to true.

Signed-off-by: Jakub Duchniewicz <j.duchniewicz@unsw.edu.au>
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lsf37 commented Dec 11, 2025

The default should be True. The RFC has it on True by default for the kernel for good reasons -- the FPU was enabled by default before and you will get hangs/crashes if you do not force the compiler to avoid FPU/SIMD instructions.

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Apologies, right - the FPU will be enabled by default and only disabled if one explicitly specifies fpu=false in the SDF.

fault_ep,
)?;

tcb.tcb_set_flags(

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given this is supposed to take a bit flags it should probably be explicitly referencing the sel4_tcbflag_fpudisabled instead of just assuming fpu is bit 0 and Boolean conversion.

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True, makes senses to be future compliant.

Signed-off-by: Jakub Duchniewicz <j.duchniewicz@unsw.edu.au>
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4 participants