On the 2015 MacBook you need to (re)compile your kernel with CONFIG_X86_INTEL_LPSS=n if running a kernel before 4.14. In all cases make sure you don't have noapic in your kernel options. If you're on any MacBook or MacBook Pro other than MacBook8,1 (2015), and you're running a kernel before 4.11, then you'll need to boot the kernel with intremap=nosid. Very simple, work in progress input driver for the SPI keyboard / trackpad found on 12' MacBooks (2015 and later) and newer MacBook Pros (late 2016 and later).