Why does rdma.service enters failed state with "Failed to load module usnic_verbs"

Issue

• Why does rdma.service enters failed state with "Failed to load module usnic_verbs"

Dec 06 17:01:54 localhost.localdomain systemd[1]: Starting Initialize the iWARP/InfiniBand/RDMA stack in the kernel...
Dec 06 17:01:57 localhost.localdomain rdma-init-kernel[771]: modprobe: ERROR: could not insert 'usnic_verbs': Operation not permitted
Dec 06 17:01:57 localhost.localdomain rdma-init-kernel[771]: Failed to load module usnic_verbs
Dec 06 17:01:57 localhost.localdomain systemd[1]: rdma.service: main process exited, code=exited, status=1/FAILURE
Dec 06 17:01:57 localhost.localdomain systemd[1]: Failed to start Initialize the iWARP/InfiniBand/RDMA stack in the kernel.
Dec 06 17:01:57 localhost.localdomain systemd[1]: Unit rdma.service entered failed state.
Dec 06 17:01:57 localhost.localdomain systemd[1]: rdma.service failed.