1. A method comprising: running secure boot code to load executable instructions into an executable memory space to perform a secure boot of a device, the executable memory space comprising at least a first memory space and a second memory space, the first memory space being loaded with at least a part of the executable instructions for enablement and disablement of a memory protection (MPU); responsive to the loading of the at least a part of the executable instructions, executing the at least a part of the executable instructions loaded in the first memory space; responsive to the execution of the at least a part of the executable instructions loaded in the first memory space, enabling the MPU, responsive to the enablement of the MPU, rendering the second memory space executable and non-writeable by the enabled MPU, and protecting the enabled MPU from any further changes by rendering the first memory space non-executable, and protecting the device from any malicious executable code by the enabled and protected MPU.