mdadm monitor keeps device locked ?

]# raidstart /dev/md0
]# mdadm --monitor --scan --daemonise > /var/run/mdadm
]# raidstop /dev/md0
/dev/md0: Device or resource busy

I first have to kill the mdadm monitor process befor i can stop the md0
(if i don't stop the raid has to resync after reboot?)

is there a better way of stopping the raid, without doing killing the
mdadm (i use killall mdadm now) ?