[SPDK] Error creating block device based on NVMe device

Hi all, 

I'm facing an error when using the command rpc.py bdev_nvme_attach_controller when creating block device based on NVMe device. But i have no problem running the examples/nvme/hello_world and examples/bdev/hello_world/hello_bdev. 

Here are the output (all commands ran in the spdk root directory),

1. First, i started the spdk_tgt (I'm using a local nvme drive)
./app/spdk_tgt/spdk_tgt &

Starting SPDK v20.04-pre git sha1 2d097539d / DPDK 19.11.0 initialization...
[ DPDK EAL parameters: spdk_tgt --no-shconf -c 0x1 --log-level=lib.eal:6 --log-level=lib.cryptodev:5 --log-level=user1:6 --iova-mode=pa --base-virtaddr=0x200000000000 --match-allocations --file-prefix=spdk_pid8592 ]
EAL: No available hugepages reported in hugepages-1048576kB
app.c: 646:spdk_app_start: *NOTICE*: Total cores available: 1
reactor.c: 371:_spdk_reactor_run: *NOTICE*: Reactor started on core 0
accel_engine.c: 227:spdk_accel_engine_initialize: *NOTICE*: Accel engine initialized to use software engine.

2. Try to create a block device using the rpc.py command
./scripts/rpc.py bdev_nvme_attach_controller -b NVMe01 -t PCIe -a 0000:04:00.0

nvme_qpair.c: 118:nvme_admin_qpair_print_command: *NOTICE*: SECURITY RECEIVE (82) sqid:0 cid:23 nsid:0 cdw10:01000100 cdw11:00000800
nvme_qpair.c: 306:spdk_nvme_qpair_print_completion: *NOTICE*: INVALID FIELD (00/02) sqid:0 cid:23 cdw0:0 sqhd:000f p:1 m:0 dnr:1
nvme_ctrlr.c:3443:spdk_nvme_ctrlr_security_receive: *ERROR*: spdk_nvme_ctrlr_cmd_security_receive failed!
bdev_nvme.c:1426:create_ctrlr: *ERROR*: Failed to initialize Opal
NVMe01n1

Here it shows error in spdk_nvme_ctrlr_cmd_security_receive and failed to initialize Opal. 

3. Then when i try checking list of currently available block devices by the rpc.py command, 
./scripts/rpc.py bdev_get_bdevs

Connection closed with partial response:


[3]+  Segmentation fault      (core dumped) ./app/spdk_tgt/spdk_tgt

it got a segmentation fault. 

I'm not sure what's the problem here, I'll appreciate any comment at all. Thank you very much. 

Best, 
Ye Hur