Error while "rxe_cfg start"

Hi, I have an SoftRoCE setup on CentOS 6.6 and its throws an error related to default_roce_mode. I have the configfs mounted and even if I try to add the version manually it throws the same error.

Here are the details -

cat /etc/*release

CentOS release 6.6 (Final)

$ ibv_devices

device node GUID


rxe0 2a6ed4fffe0feba7

mount

.

.

.

none on /sys/kernel/config type configfs (rw)

rxe_cfg start

IBOE V2

tee: /sys/kernel/config/rdma_cm/rxe0/default_roce_mode: Invalid argument

Name Link Driver Speed NMTU IPv4_addr RDEV RMTU

eth0 no tg3 1500

eth1 no tg3 1500

eth2 no tg3 1500

eth3 no tg3 1500

eth4 no tg3 1500

eth5 yes tg3 1500 10.213.41.228 rxe0 1024 (3)

Trying to add the version manually -

mkdir /sys/kernel/config/rdma_cm/rxe0

cat /sys/kernel/config/rdma_cm/rxe0/default_roce_mode

IB/RoCE V1

echo IBOE V2 > /sys/kernel/config/rdma_cm/rxe0/default_roce_mode

bash: echo: write error: Invalid argument

Can you please share the possible cause of this error.