Test team tried to run the following command and got the error:

nose2 --verbose --start-dir tests nvme_compare_test

test_write_zeros (nvme_writezeros_test.TestNVMeWriteZeros)
Testcae main ...
Using nvme binary 'nvme'
ERROR

======================================================================
ERROR: test_write_zeros (nvme_writezeros_test.TestNVMeWriteZeros)
Testcae main

Traceback (most recent call last):
File "/home/nvme-cli/tests/nvme_writezeros_test.py", line 52, in setUp
super().setUp()
File "/home/nvme-cli/tests/nvme_test_io.py", line 44, in setUp
super().setUp()
File "/home/nvme-cli/tests/nvme_test.py", line 80, in setUp
self.create_and_attach_default_ns()
File "/home/nvme-cli/tests/nvme_test.py", line 109, in create_and_attach_default_ns
err = self.create_and_validate_ns(self.default_nsid,
File "/home/nvme-cli/tests/nvme_test.py", line 379, in create_and_validate_ns
json_output = json.loads(proc.stdout.read())
File "/usr/lib64/python3.9/json/init.py", line 346, in loads
return _default_decoder.decode(s)
File "/usr/lib64/python3.9/json/decoder.py", line 337, in decode
obj, end = self.raw_decode(s, idx=_w(s, 0).end())
File "/usr/lib64/python3.9/json/decoder.py", line 355, in raw_decode
raise JSONDecodeError("Expecting value", s, err.value) from None
json.decoder.JSONDecodeError: Expecting value: line 1 column 1 (char 0)

Ran 1 test in 0.961s

FAILED (errors=1)

When creating a namespace for the first time, output is text: create-ns: Success, created nsid:1
nvme create-ns /dev/nvme4 --nsze=390703446 --ncap=390703446 --flbas=0 --dps=0 --output-format=json
create-ns: Success, created nsid:1

When creating a namespace for the second time, output is in json format.
nvme create-ns /dev/nvme4 --nsze=390703446 --ncap=390703446 --flbas=0 --dps=0 --output-format=json
{
"status: 8469":[
{
"error":"Namespace Insufficient Capacity: Creating the namespace requires more free space than is currently available",
"type":"nvme"
}
]
}

We hits the ERROR when trying to call " json.loads(proc.stdout.read())." to read text.
So the patch fix the issue: use proc.stdout.read() instead of json.loads(proc.stdout.read()).

Signed-off-by: Wen Xiong[email protected]