Patent ID: 7660912

Claim:
A method of isolating a plurality of input/output adapter units of a data processing system, said data processing system comprising a set of processors, a plurality of host bridges, and a plurality of input/output adapters, wherein each of the input/output adapters is connected to one of the host bridges, and each of the host bridges is connected to one or more of the input/output adapters, said method comprising the steps of: partitioning the data processing system into a group of partitions; assigning each of the host bridges to one and only one of the partitions; assigning to each of the host bridges a respective Unit ID; providing a table having a series of entries, each of the entries including a Unit ID identifying one of the host bridges; one of the input/output adapters generating a request having a request ID and a specified address, and sending said request to the one of the host bridges to which said one of the input/output adapters is connected; said one of the host bridges generating a request packet to satisfy the request, putting into the request packet the Unit ID of said one of the host bridges and the specified address from the request, and sending the request packet to one of the processors; and said one of the processors receiving the request packet, using said specified address from the request packet as an index into said tables, to obtain one of the Unit IDs from said table, and comparing the Unit ID obtained from the table with the Unit ID of said one of the host bridges to determine whether to route a response packet back said one of the host bridges.