My system setup are the following.
OS: ubuntu 14.04
Kernel: linux-headers-3.19.5-031905-generic
MLNX_OFED Driver: 2.4-1.0.4
and the setup works on ipoib, srp, iscsi & iSER. However, I am not able to get ib_srpt to work with mlnx_ofed 2.4 (but able to make it work with ubuntu distro ofed 2.2-1)
The trick is download the latest supported 3.19 kernel from ubuntu main ppa: Index of /~kernel-ppa/mainline/v3.19.5-vivid
And download the latest mlnx_ofed 2.4 driver for ubuntu 14.10, after extra the files, change distro file from ubuntu 14.10 to ubuntu 14.04.
Then you can run the mlnxofedinstall