Issue 1:
Checklist

I have read the relevant section in the

contribution guide

on reporting bugs.

I have checked the issues list

for similar or identical bug reports.

I have checked the pull requests list

for existing proposed fixes.

I have checked the commit log

to find out if the bug was already fixed in the master branch.

I have included all related issues and possible duplicate issues

in this issue (If there are none, check this box anyway).

Mandatory Debugging Information

I have included the output of celery -A proj report in the issue.

(if you are not able to do this, then at least specify the Celery

version affected).

I have verified that the issue exists against the master branch of Celery.

I have included the contents of pip freeze in the issue.

I have included all the versions of all the external dependencies required

to reproduce this bug.

Optional Debugging Information

I have tried reproducing the issue on more than one Python version

and/or implementation.

I have tried reproducing the issue on more than one message broker and/or

result backend.

I have tried reproducing the issue on more than one version of the message

broker and/or result backend.

I have tried reproducing the issue on more than one operating system.

I have tried reproducing the issue on more than one workers pool.

I have tried reproducing the issue with autoscaling, retries,

ETA/Countdown & rate limits disabled.

I have tried reproducing the issue after downgrading

and/or upgrading Celery and its dependencies.

Related Issues and Possible Duplicates

Related Issues

#5330

Possible Duplicates

None

Environment & Settings

Celery version:4.3.0

celery report Output:

software -> celery:4.3.0 (rhubarb) kombu:4.6.4 py:3.5.6
billiard:3.6.1.0 py-amqp:2.5.1
platform -> system:Linux arch:64bit, ELF
kernel version:4.19.71-1-lts imp:CPython
loader -> celery.loaders.default.Loader
settings -> transport:amqp results:disabled

Steps to Reproduce

Required Dependencies

Minimal Python Version: 3.5.6

Minimal Celery Version: 4.3.0

Minimal Kombu Version: 4.6.4

Minimal Broker Version: RabbitMQ 3.7.15

Minimal Result Backend Version: 10.4.7-MariaDB

Minimal OS and/or Kernel Version: Linux 4.19.71-1-lts

Python Packages

pip freeze Output:

amqp==2.5.1
asn1crypto==0.24.0
Babel==2.7.0
bcrypt==3.1.7
billiard==3.6.1.0
celery==4.3.0
certifi==2019.9.11
cffi==1.12.3
chardet==3.0.4
cryptography==2.7
django-celery-results==1.1.2
flower==0.9.3
idna==2.8
importlib-metadata==0.22
kombu==4.6.4
more-itertools==7.2.0
mysqlclient==1.4.4
paramiko==2.6.0
pycparser==2.19
PyNaCl==1.3.0
pytz==2019.2
requests==2.22.0
requests-toolbelt==0.9.1
six==1.12.0
SQLAlchemy==1.3.8
tornado==5.1.1
urllib3==1.25.3
vine==1.3.0
websockets==7.0
zipp==0.6.0

Other Dependencies

N/A

Minimally Reproducible Test Case

@app.task
def add(x, y):
return x + y

@app.task
def test():
result_set = ResultSet([])
add_tasks = add.starmap((i, i) for i in range(10))
add_result = add_tasks.apply_async()
result_set.add(add_result)
return result_set.get(disable_sync_subtasks=False)

Expected Behavior

The tasks runs successfully, with the acceptance of possible deadlock

Actual Behavior

Traceback (most recent call last):
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/app/trace.py", line 385, in trace_task
R = retval = fun(*args, **kwargs)
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/app/trace.py", line 648, in __protected_call__
return self.run(*args, **kwargs)
File "/home/gsfish/work/netease/project/scan_detect/tasks.py", line 106, in test
return result_set.get(disable_sync_subtasks=False)
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/result.py", line 697, in get
on_interval=on_interval,
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/result.py", line 765, in join
interval=interval, no_ack=no_ack, on_interval=on_interval,
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/result.py", line 205, in get
assert_will_not_block()
File "/home/gsfish/.pyenv/versions/scan_detect/lib/python3.5/site-packages/celery/result.py", line 41, in assert_will_not_block
raise RuntimeError(E_WOULDBLOCK)
RuntimeError: Never call result.get() within a task!
See http://docs.celeryq.org/en/latest/userguide/tasks.html#task-synchronous-subtasks

Issue 2:
Checklist

I have read the relevant section in the

contribution guide

on reporting bugs.

I have checked the issues list

for similar or identical bug reports.

I have checked the pull requests list

for existing proposed fixes.

I have checked the commit log

to find out if the bug was already fixed in the master branch.

This relates to 4.3.0, not 4.4.x

I have included all related issues and possible duplicate issues

in this issue (If there are none, check this box anyway).

Mandatory Debugging Information

I have included the output of celery -A proj report in the issue.

(if you are not able to do this, then at least specify the Celery

version affected).

I have verified that the issue exists against the master branch of Celery.

I have included the contents of pip freeze in the issue.

I have included all the versions of all the external dependencies required

to reproduce this bug.

Optional Debugging Information

I have tried reproducing the issue on more than one Python version

and/or implementation.

I have tried reproducing the issue on more than one message broker and/or

result backend.

I have tried reproducing the issue on more than one version of the message

broker and/or result backend.

I have tried reproducing the issue on more than one operating system.

I have tried reproducing the issue on more than one workers pool.

I have tried reproducing the issue with autoscaling, retries,

ETA/Countdown & rate limits disabled.

I have tried reproducing the issue after downgrading

and/or upgrading Celery and its dependencies.

Related Issues and Possible Duplicates

Related Issues

celery/kombu#1052

Possible Duplicates

None

Environment & Settings

Celery version: 4.3.0 (rhubarb)

Output:

software -> celery:4.3.0 (rhubarb) kombu:4.6.0 py:3.7.3
billiard:3.6.0.0 redis:3.2.1
platform -> system:Linux arch:64bit
kernel version:4.15.0-50-generic imp:CPython
loader -> celery.loaders.app.AppLoader
settings -> transport:redis results:redis://localhost:6379/1

Steps to Reproduce

Required Dependencies

Minimal Python Version: Unknown

Minimal Celery Version: N/A or Unknown

Minimal Kombu Version: 4.6.0

Minimal Broker Version: N/A or Unknown

Minimal Result Backend Version: N/A or Unknown

Minimal OS and/or Kernel Version: N/A or Unknown

Minimal Broker Client Version: N/A or Unknown

Minimal Result Backend Client Version: N/A or Unknown

Python Packages

pip freeze Output:

flower==0.9.3
- babel [required: >=1.0,<3.0.0, installed: 2.7.0]
- pytz [required: >=2015.7, installed: 2019.1]
- celery [required: >=3.1.0, installed: 4.3.0]
- billiard [required: >=3.6.0,<4.0, installed: 3.6.0.0]
- kombu [required: >=4.4.0,<5.0, installed: 4.6.0]
- amqp [required: >=2.5.0,<3.0, installed: 2.5.0]
- vine [required: >=1.1.3,<5.0.0a1, installed: 1.3.0]
- pytz [required: >dev, installed: 2019.1]
- vine [required: >=1.3.0, installed: 1.3.0]
- pytz [required: Any, installed: 2019.1]
- tornado [required: >=4.2.0,<6.0.0, installed: 5.1.1]

Other Dependencies

N/A

Minimally Reproducible Test Case

1. run celery 4.3.0 with a fresh install (make sure you got kombu 4.6.0)
2. run celery inspect ping
3. profit.

Expected Behavior

Ping should work

Actual Behavior

ping says no nodes resonded