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Minimum size (and alignment when applicable) of an ARM MPU region, which guards the stack of a thread that is using the Floating Point (FP) context. The width of the guard is set to 128, to accommodate the length of a Cortex-M exception stack frame when the floating point context is active. The FP context is only stacked in sharing FP registers mode, therefore, the option is applicable only when FPU_SHARING is selected.

Direct dependencies¶

MPU_STACK_GUARD && FPU_SHARING && ARM_MPU && CPU_HAS_MPU && CPU_CORTEX_M && !ARM64 && ARM

(Includes any dependencies from ifs and menus.)

Default¶

128

Kconfig definition¶

At arch/arm/core/aarch32/cortex_m/mpu/Kconfig:64

Included via Kconfig:8 → Kconfig.zephyr:29 → arch/Kconfig:12 → arch/arm/Kconfig:42 → arch/arm/core/aarch32/Kconfig:237 → arch/arm/core/aarch32/cortex_m/Kconfig:308

Menu path: (Top) → ARM Options → Thread Stack Guards

config MPU_STACK_GUARD_MIN_SIZE_FLOAT
    int
    default 128
    depends on MPU_STACK_GUARD && FPU_SHARING && ARM_MPU && CPU_HAS_MPU && CPU_CORTEX_M && !ARM64 && ARM
    help
      Minimum size (and alignment when applicable) of an ARM MPU
      region, which guards the stack of a thread that is using the
      Floating Point (FP) context. The width of the guard is set to
      128, to accommodate the length of a Cortex-M exception stack
      frame when the floating point context is active. The FP context
      is only stacked in sharing FP registers mode, therefore, the
      option is applicable only when FPU_SHARING is selected.

(The ‘depends on’ condition includes propagated dependencies from ifs and menus.)