* Mark the I/O Pdir entries invalid and blow away the corresponding I/O
* TLB entries.
*
- * FIXME: at some threshhold it might be "cheaper" to just blow
+ * FIXME: at some threshold it might be "cheaper" to just blow
* away the entire I/O TLB instead of individual entries.
*
* FIXME: Uturn has 256 TLB entries. We don't need to purge every