Fail to run ibnetdiscover under ibumad2sim

[tzafrir-mellanox]

Hi,

The following worked fine with rdma-core v55 but fails with rdma-core v56. I guess there's a new flow to catch?

My original test:

./ibsim/ibsim -s -n net-examples/net.1 &

D_LIBRARY_PATH=$RDMA_CORE_DIR/build-deb/lib LD_PRELOAD=$PWD/umad2sim/libumad2sim.so $RDMA_CORE_DIR/build-deb/bin/ibnetdiscover

A trace with some debug prints I added:

ibwarn: [245271] sim_connect: attached as client 0 at node "Switch1"
ibwarn: [245271] umad_get_smi_gsi_pairs: Tzafrir: cas_found: 1
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0)
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get uint from /sys/class/infiniband/ibsim0/node_type: node_type
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/fw_ver: fw_ver
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/hw_rev: hw_ver
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/hca_type: ca_type
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get guid from /sys/class/infiniband/ibsim0/node_guid: node_guid
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get guid from /sys/class/infiniband/ibsim0/sys_image_guid: system_guid
ibwarn: [245271] get_ca: Tzafrir: Opening dir /sys/class/infiniband/ibsim0/ports:
ibwarn: [245271] get_ca: Tzafrir: Scanning dir /sys/class/infiniband/ibsim0/ports:
ibwarn: [245271] get_ca: Tzafrir: Scanning dir /sys/class/infiniband/ibsim0/ports: get 3
ibwarn: [245271] get_ca: Tzafrir: namelist[0]
ibwarn: [245271] get_ca: Tzafrir: namelist[1]
ibwarn: [245271] get_ca: Tzafrir: namelist[2]
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: not . or ..
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: d_name sane
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: allocated port
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: get_port, portnum: 0
ibwarn: [245271] umad_get_smi_gsi_pairs: Tzafrir: Checking c_idx: 0
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0)
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get uint from /sys/class/infiniband/ibsim0/node_type: node_type
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/fw_ver: fw_ver
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/hw_rev: hw_ver
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get string from /sys/class/infiniband/ibsim0/hca_type: ca_type
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get guid from /sys/class/infiniband/ibsim0/node_guid: node_guid
ibwarn: [245271] get_ca: Tzafrir: get_ca(ibsim0): get guid from /sys/class/infiniband/ibsim0/sys_image_guid: system_guid
ibwarn: [245271] get_ca: Tzafrir: Opening dir /sys/class/infiniband/ibsim0/ports:
ibwarn: [245271] get_ca: Tzafrir: Scanning dir /sys/class/infiniband/ibsim0/ports:
ibwarn: [245271] get_ca: Tzafrir: Scanning dir /sys/class/infiniband/ibsim0/ports: get 3
ibwarn: [245271] get_ca: Tzafrir: namelist[0]
ibwarn: [245271] get_ca: Tzafrir: namelist[1]
ibwarn: [245271] get_ca: Tzafrir: namelist[2]
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: not . or ..
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: d_name sane
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: allocated port
ibwarn: [245271] get_ca: Tzafrir: namelist[2]: get_port, portnum: 0
ibwarn: [245271] umad_get_smi_gsi_pairs: Tzafrir: Checking c_idx: 0: get_umad_ca is good: numports: 0
ibwarn: [245271] umad_get_smi_gsi_pair_by_ca_name: Tzafrir: num_cas not > 0: 0
ibwarn: [245271] get_ca: Tzafrir: get_ca()
ibwarn: [245271] get_ca: Tzafrir: get_ca(): get uint from /sys/class/infiniband//node_type: node_type
ibwarn: [245271] get_smi_gsi_pair: Can't open SMI UMAD port (No such device) (:0)
ibwarn: [245271] mad_rpc_open_port2: can't open UMAD port ((null):0)
./libibnetdisc/ibnetdisc.c:799; can't open MAD port ((null):0)
/home/tzafrirc/Proj/Salsa/hpc/rdma-core/rdma-core/build-deb/bin/ibnetdiscover: iberror: failed: discover failed