1. A controller hub comprising: storage logic to hold a table, the table to include an entry to associate a memory location in a host processor with a storage location in an input/output (I/O) device; monitor logic coupled to the storage logic to monitor an access to the memory location by the host processor, the monitor logic to request a value held in the memory location from the host processor and to store the value in the entry in response to the access to the memory location being completed; and write logic coupled to the monitor logic to provide the value to the I/O device in response to the value being stored in the entry.