Can you check this dir?
# ls -l /dev/infiniband/
total 0
crw-rw---- 1 root root 231, 64 Jan 6 18:57 issm0
crw-rw---- 1 root root 231, 65 Jan 6 18:57 issm1
crw-rw-rw- 1 root root 10, 56 Dec 28 00:17 rdma_cm
crw-rw-rw- 1 root root 231, 224 Dec 28 00:17 ucm0
crw-rw-rw- 1 root root 231, 0 Jan 6 18:57 umad0
crw-rw-rw- 1 root root 231, 1 Jan 6 18:57 umad1
crw-rw-rw- 1 root root 231, 192 Dec 28 00:17 uverbs0
Those are created by udev and the rules should look like this.
If those rules are missing or have wrong permissions, that might be the cause.
# cat /etc/udev/rules.d/90-ib.rules
KERNEL=="umad*", NAME="infiniband/%k" MODE="0666"
KERNEL=="issm*", NAME="infiniband/%k"
KERNEL=="ucm*", NAME="infiniband/%k", MODE="0666"
KERNEL=="uverbs*", NAME="infiniband/%k", MODE="0666"
KERNEL=="ucma", NAME="infiniband/%k", MODE="0666"
KERNEL=="rdma_cm", NAME="infiniband/%k", MODE="0666"