[Bug]: salt.ext.tornado.concurrent.Future exception was never retrieved

[jmemu]

What happened?

Updated minion from 3006.23 to 3006.25

Running salt-call state.highstate shows this in the logs,

2026-05-19 03:43:32,928 [salt.transport.ipc:360 ][DEBUG   ][48650] Closing IPCMessageClient instance
2026-05-19 03:43:32,930 [tornado.application:353 ][ERROR   ][48650] Future <salt.ext.tornado.concurrent.Future object at 0x7fb0a4b93940> exception was never retrieved: Traceback (most recent call last):
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 333, in _connect
    self._connecting_future.set_result(True)
AttributeError: 'NoneType' object has no attribute 'set_result'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/gen.py", line 1070, in run
    yielded = self.gen.send(value)
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 343, in _connect
    self._connecting_future.set_exception(e)
AttributeError: 'NoneType' object has no attribute 'set_exception'

Type of salt install

Official rpm

Major version

3006.x

What supported OS are you seeing the problem on? Can select multiple. (If bug appears on an unsupported OS, please open a GitHub Discussion instead)

rockylinux-9

salt --versions-report output

# salt-call --versions-report output
Salt Version:
          Salt: 3006.25

Python Version:
        Python: 3.10.20 (main, Apr 22 2026, 05:54:37) [GCC 11.2.0]

Dependency Versions:
          cffi: 2.0.0
      cherrypy: unknown
  cryptography: 46.0.7
      dateutil: 2.8.2
     docker-py: Not Installed
         gitdb: 4.0.12
     gitpython: Not Installed
        Jinja2: 3.1.6
       libgit2: Not Installed
  looseversion: 1.3.0
      M2Crypto: Not Installed
          Mako: 1.3.12
       msgpack: 1.0.7
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 24.0
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.23.0
        pygit2: Not Installed
  python-gnupg: 0.5.2
        PyYAML: 6.0.1
         PyZMQ: 25.1.2
        relenv: 0.22.8
         smmap: 5.0.2
       timelib: 0.3.0
       Tornado: 6.5.5
           ZMQ: 4.3.4

System Versions:
          dist: rocky 9.7 Blue Onyx
        locale: utf-8
       machine: x86_64
       release: 5.14.0-611.49.1.el9_7.x86_64
        system: Linux
       version: Rocky Linux 9.7 Blue Onyx

[andreasdijkman]

I can confirm that this bug is also present in 3006.24. In this case on Red Hat Enterprise Linux.

Salt Version:
          Salt: 3006.24

Python Version:
        Python: 3.10.20 (main, Apr 22 2026, 05:54:37) [GCC 11.2.0]

Dependency Versions:
          cffi: 2.0.0
      cherrypy: unknown
  cryptography: 46.0.7
      dateutil: 2.8.2
     docker-py: Not Installed
         gitdb: 4.0.12
     gitpython: Not Installed
        Jinja2: 3.1.6
       libgit2: Not Installed
  looseversion: 1.3.0
      M2Crypto: Not Installed
          Mako: Not Installed
       msgpack: 1.0.7
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 24.0
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.23.0
        pygit2: Not Installed
  python-gnupg: 0.5.2
        PyYAML: 6.0.1
         PyZMQ: 25.1.2
        relenv: 0.22.8
         smmap: 5.0.2
       timelib: 0.3.0
       Tornado: 6.5.5
           ZMQ: 4.3.4

System Versions:
          dist: rhel 10.1 Coughlan
        locale: utf-8
       machine: x86_64
       release: 6.12.0-124.55.1.el10_1.x86_64
        system: Linux
       version: Red Hat Enterprise Linux 10.1 Coughlan

[Ivca50V]

Same for 3006.25 during salt-cloud provisioning. AlmaLinux distro.

Salt Version:
Salt: 3006.25

Python Version:
Python: 3.10.20 (main, Apr 22 2026, 05:54:37) [GCC 11.2.0]

Dependency Versions:
cffi: 2.0.0
cherrypy: unknown
cryptography: 46.0.7
dateutil: 2.8.2
docker-py: Not Installed
gitdb: 4.0.12
gitpython: Not Installed
Jinja2: 3.1.6
libgit2: Not Installed
looseversion: 1.3.0
M2Crypto: Not Installed
Mako: Not Installed
msgpack: 1.0.7
msgpack-pure: Not Installed
mysql-python: Not Installed
packaging: 24.0
pycparser: 2.21
pycrypto: Not Installed
pycryptodome: 3.23.0
pygit2: Not Installed
python-gnupg: 0.5.2
PyYAML: 6.0.1
PyZMQ: 25.1.2
relenv: 0.22.8
smmap: 5.0.2
timelib: 0.3.0
Tornado: 6.5.5
ZMQ: 4.3.4

System Versions:
dist: almalinux 9.7 Moss Jungle Cat
locale: utf-8
machine: x86_64
release: 5.14.0-611.55.1.el9_7.x86_64
system: Linux
version: AlmaLinux 9.7 Moss Jungle Cat

[sudberg]

Also affecting RHEL8.

Official RPM package install.

3006.24 gives a different error:

[ERROR   ] Future <salt.ext.tornado.concurrent.Future object at 0x7fb5654b4340> exception was never retrieved: Traceback (most recent call last):
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 333, in _connect
    self._connecting_future.set_result(True)
AttributeError: 'NoneType' object has no attribute 'set_result'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/gen.py", line 1070, in run
    yielded = self.gen.send(value)
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 343, in _connect
    self._connecting_future.set_exception(e)
AttributeError: 'NoneType' object has no attribute 'set_exception'

to v3006.25:

[ERROR   ] Exception in callback functools.partial(<function wrap.<locals>.null_wrapper at 0x7f86e5e789d0>, <salt.ext.tornado.concurrent.Future object at 0x7f86e5d9cc40>)
Traceback (most recent call last):
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/ioloop.py", line 606, in _run_callback
    ret = callback()
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/stack_context.py", line 278, in null_wrapper
    return fn(*args, **kwargs)
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/ioloop.py", line 628, in _discard_future_result
    future.result()
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/concurrent.py", line 249, in result
    raise_exc_info(self._exc_info)
  File "<string>", line 4, in raise_exc_info
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/gen.py", line 1064, in run
    yielded = self.gen.throw(*exc_info)
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 441, in send
    yield self.connect()
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/gen.py", line 1056, in run
    value = future.result()
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/concurrent.py", line 249, in result
    raise_exc_info(self._exc_info)
  File "<string>", line 4, in raise_exc_info
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/transport/ipc.py", line 332, in _connect
    yield self.stream.connect(sock_addr)
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/gen.py", line 1056, in run
    value = future.result()
  File "/opt/saltstack/salt/lib/python3.10/site-packages/salt/ext/tornado/concurrent.py", line 249, in result
    raise_exc_info(self._exc_info)
  File "<string>", line 4, in raise_exc_info
salt.ext.tornado.iostream.StreamClosedError: Stream is closed

Salt Version:
          Salt: 3006.25

Python Version:
        Python: 3.10.20 (main, Apr 22 2026, 05:54:37) [GCC 11.2.0]

Dependency Versions:
          cffi: 2.0.0
      cherrypy: unknown
  cryptography: 46.0.7
      dateutil: 2.8.2
     docker-py: Not Installed
         gitdb: 4.0.12
     gitpython: 3.1.46
        Jinja2: 3.1.6
       libgit2: Not Installed
  looseversion: 1.3.0
      M2Crypto: Not Installed
          Mako: Not Installed
       msgpack: 1.0.7
  msgpack-pure: Not Installed
  mysql-python: Not Installed
     packaging: 24.0
     pycparser: 2.21
      pycrypto: Not Installed
  pycryptodome: 3.23.0
        pygit2: Not Installed
  python-gnupg: 0.5.2
        PyYAML: 6.0.1
         PyZMQ: 25.1.2
        relenv: 0.22.8
         smmap: 5.0.2
       timelib: 0.3.0
       Tornado: 6.5.5
           ZMQ: 4.3.4

System Versions:
          dist: rhel 8.9 Ootpa
        locale: utf-8
       machine: x86_64
       release: 4.18.0-513.11.1.el8_9.x86_64
        system: Linux
       version: Red Hat Enterprise Linux 8.9 Ootpa