Run
# yum install "InfiniBand Support"
See this post
HowTo setup RoCE connection using Inbox driver (RHEL, Ubuntu)
You can also install MLNX_OFED, see Mellanox website for the driver package.
Click here, and follow the links.
Mellanox Products: Mellanox OpenFabrics Enterprise Distribution for Linux (MLNX_OFED)
Thanks,
Ophir.