printing the comm field of the `current` task_struct, Linux kernel

I'm trying to print the comm field of the current task_struct to print the name of a process. Then, using current->parent, I want to do the same thing for all the current process's ancestors.

Here's what I've got so far:

while (there is still an ancestor of current to print) {
...
   printk("Name: %s", current_task->comm);
... 
}

And here's the result (pid shown to the left of the process names):

As you can see, the first and last processes aren't printing correctly. I understand why the first one is being truncated -- current->comm is an array of 16 chars, and so there is simply no room for the final "r" in process_ancestor (the name of my program). However, I don't understand why swapper has the null terminator appended to it. Is there any chance that this is actually the name of the process? Or is something else going wrong?

What you see is exactly the process name, the swapper process runs each instance per CPU on a SMP system, and they are distinguished by appending the process number to it, so on the 1st CPU, the process is swapper/0, on the 2nd it would be swapper/1, and so on. You can find out in the kernel source:

http://lxr.free-electrons.com/source/kernel/sched/core.c?v=3.5#L5136

#if defined(CONFIG_SMP)
     sprintf(idle->comm, "%s/%d", INIT_TASK_COMM, cpu);
#endif

Here INIT_TASK_COMMON is defined as "swapper" in header file, and cpu is current cpu number.