futex_wait

sys_futex_wait(void *uaddr, unsigned long val, unsigned long mask, unsigned int flags, struct __kernel_timespec *timespec, clockid_t clockid)

register	value
`r12`	455, the syscall number
`r5`	void *uaddr
`r6`	unsigned long val
`r7`	unsigned long mask
`r8`	unsigned int flags
`r9`	struct __kernel_timespec *timespec
`r10`	clockid_t clockid
`r3`	the return value

Then run brki r14,8 to enter the kernel.

Same syscall on other architectures