rdma_rxe usage problem

[Alexander Kalentyev <comrad.karlovich@xxxxxxxxx>]

I am trying to install and use soft RoCE for development purposes
(right now on a localhost).
I installed rdma-core on a MANJARO system from AUR.
Then I did:

sudo modprobe rdma_rxe
sudo rdma link add rxe0 type rxe netdev wlp60s0

then ibstat shows:
CA 'rxe0'
        CA type:
        Number of ports: 1
        Firmware version:
        Hardware version:
        Node GUID: 0x4a51c5fffef6e159
        System image GUID: 0x4a51c5fffef6e159
        Port 1:
                State: Active
                Physical state: LinkUp
                Rate: 2.5
                Base lid: 0
                LMC: 0
                SM lid: 0
                Capability mask: 0x00010000
                Port GUID: 0x4a51c5fffef6e159
                Link layer: Ethernet

But launching any example I always get an error by call of: ibv_modify_qp
with an attempt to modify QP state to RTR (for example by launching
.ibv_rc_pingpong)
The type of the error is EINVAL.
I believe I miss something very obvious.