ISSUES WITH ACCESSING CPU INDEX

```
Description: The CPU number is accessed usually with the macro this_cpu().
The returned CPU number is then used for various things,
typically as an array index. However, if pre-emption is
not disabled,then it is possible that a context switch
could occur and that logic could run on another CPU with
possible fatal consequences.

We need to evaluate all use of this_cpu() and assure that
it is used in a way that guarantees the the code continues
to execute on the same CPU.

Status: Open
Prioity: Medium. This is a logical problem but I have never seen
an bugs caused by this. But I believe that failures are
possible.
```