kexec_load

load a new kernel for later execution

sys_kexec_load(unsigned long entry, unsigned long nr_segments, struct kexec_segment *segments, unsigned long flags)

register	value
`r20`	300, the syscall number
`r26`	unsigned long entry
`r25`	unsigned long nr_segments
`r24`	struct kexec_segment *segments
`r23`	unsigned long flags
`r28`	the return value

Then run ble 0x100(%sr2, %r0) to enter the kernel.

Same syscall on other architectures