A computer implementing a kernel, the computer including: (a) a processor that is configured to run processes in kernel mode and to run other processes not in kernel mode, wherein the processor is configured to run in the kernel mode the following processes: (i) selecting a rule out of a group of rules that is stored in a kernel memory of the computer, in response to system call information that pertains to a system call made to a kernel entity of the kernel; (ii) assigning a priority to the system call in response to the rule selected; and (iii) selectively enabling transmission of the system call to a hardware device of the computerized entity, in response to the priority assigned to the system call; (b) a memory that includes the memory kernel; and (c) the hardware device that is configured to execute the system call, wherein execution of the system call by the hardware device results in modifying a state of the hardware device.