How to cause kernel panic with a single command?

Question

Is it possible to cause a kernel panic with a single command line?

What would be the most straightforward such command for a sudoing user and what would it be for a regular user, if any?

Scenarios that suggest downloading something as a part of the command do not count.

Answer 1

FreeBSD:

sysctl debug.kdb.panic=1

Linux (more info here):

echo c > /proc/sysrq-trigger

Answer 2

The kernel is meant to keep running no matter what. So any way to cause a kernel panic by user interaction (other than deliberate vandalism by all-powerful root, like Bruce Ediger jokinkly proposes, and most kernels today are built so most of those pranks won't work in the first place) is an extremely serious bug, that would get fixed fast.

Answer 3

compile the following code into a module and insmod it, sure you should get a panic:

static int crash_module_init(void)

{
     printf("crash module starting\n");
     int *p = 0;

     printk("%d\n", *p);

     return 0;
}

static void crash_module_exit(void)
{
    printf("crash module exiting\n");
}

module_init(crash_module_init);
module_exit(crash_module_exit);