Mgmt_class for MAD packet in MLX4 driver


From the IB specification , MAD packet Mgmt_class values are defined in

Table 113 Management Class Values

ComMgt 0x07 Communication Management

Subn 0x81 Subnet Management class (Directed route)

The MAD data structure different for both Mgmt_classes.

The Subn contains Extra data fields like hop_ptr, hop_cnt … Defined in the ib_smp structure /include/rdma/ib_smi.h

The ComMgt is for regular MAD data packets Defined in ib_mad_hdr /include/rdma/ib_mad.h

when I receive MAD packets from Mellanox (mlx4) with rping. we are observing Mgmt_class as 0x07, But data offset as per Subn class.

The Mellnox driver ( drivers/infiniband/hw/mlx4/main.c ) using ib_smp structure instead of ib_mad_hdr .

Any reason for this ?



Hello Rama,

What driver version are you currently running?

How are you observing the Mgmt_class with rping?

What do you mean by “data offset as per Subn class”?

Is there a current issue?

What are you trying to accomplish?