function terminates the running system.
style format string.
The message is printed to the console and the location
is set to the address of the message text for retrieval from the OS
If the kernel debugger is installed control is passed to it, otherwise
an attempt to save a core dump of the OS to a configured dump device
is called twice (from the disk sync routines, for example) the system is
rebooted without syncing the disks.