request/response pairs. The upper 32 bits are reserved for use by
the kernel and will be overwritten before a MAD is sent.
+P_Key Index Handling
+
+ The old ib_umad interface did not allow setting the P_Key index for
+ MADs that are sent and did not provide a way for obtaining the P_Key
+ index of received MADs. A new layout for struct ib_user_mad_hdr
+ with a pkey_index member has been defined; however, to preserve
+ binary compatibility with older applications, this new layout will
+ not be used unless the IB_USER_MAD_ENABLE_PKEY ioctl is called
+ before a file descriptor is used for anything else.
+
+ In September 2008, the IB_USER_MAD_ABI_VERSION will be incremented
+ to 6, the new layout of struct ib_user_mad_hdr will be used by
+ default, and the IB_USER_MAD_ENABLE_PKEY ioctl will be removed.
+
Setting IsSM Capability Bit
To set the IsSM capability bit for a port, simply open the