Function sunrise_kernel::start

#[no_mangle]pub unsafe extern "C" fn start() -> !

The entry point of our kernel.

This function is jump'd into from the bootstrap code, which:

• enabled paging,
• gave us a valid KernelStack,
• mapped grub's multiboot information structure in KernelLand (its address in $ebx),

What we do is just bzero the .bss, and call a rust function, passing it the content of $ebx.

Safety

May only be called once, as the program entrypoint.