Matt Wang (@witallwang) started discussion #110
Here we are getting to the end of the setup_arch function. The rest of function of course is important, but details about these stuff will not will not be included in this part. We will just take a short look on these functions, because although they are important as I wrote above, but they cover non-generic kernel features related with the NUMA, SMP, ACPI and APICs, etc. First of all, the next call of the init_apic_mappings function. As we can understand this function sets the address of the local APIC. The next is x86_io_apic_ops.init and this function initializes I/O APIC. Please note that we will see all details related with APIC in the chapter about interrupts and exceptions handling. In the next step we reserve standard I/O resources like DMA, TIMER, FPU, etc., with the call of the x86_init.resources.reserve_resources function. Following is mcheck_init function initializes Machine check Exception and the last is register_refined_jiffies which registers jiffy (There will be separate chapter about timers in the kernel).