Hello David, In fact, I was not able to reproduce this bug on my machine, even on the same version you reported the problem:
# /usr/sbin/nvme list --output-format=json
# echo $?
0
#/usr/sbin/nvme --version
nvme version 1.0
# ndctl dpkg -l | grep nvme-cli
ii nvme-cli 1.0-3
ppc64el userspace tooling to control NVMe drives
Are you able to reproduce this issue on the upstream nvme-cli?
