Version-Release number of selected component:
dnf-0.4.15-1.fc20

Additional info:
reporter:       libreport-2.1.12
cmdline:        /usr/bin/python /usr/bin/dnf -v makecache timer
executable:     /usr/bin/dnf
kernel:         3.13.4-200.fc20.i686+PAE
runlevel:       N 5
type:           Python
uid:            0

Truncated backtrace:
repo.py:312:start:AttributeError: 'NoneType' object has no attribute 'start'

Traceback (most recent call last):
  File "/usr/bin/dnf", line 35, in <module>
    main.user_main(sys.argv[1:], exit_code=True)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 242, in user_main
    errcode = main(args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 64, in main
    return _main(base, args)
  File "/usr/lib/python2.7/site-packages/dnf/cli/main.py", line 124, in _main
    cli.run()
  File "/usr/lib/python2.7/site-packages/dnf/cli/cli.py", line 1459, in run
    return self.command.run(self.base.extcmds)
  File "/usr/lib/python2.7/site-packages/dnf/cli/commands.py", line 852, in run
    self.base.fill_sack() # performs the md sync
  File "/usr/lib/python2.7/site-packages/dnf/base.py", line 213, in fill_sack
    self._add_repo_to_sack(r.id)
  File "/usr/lib/python2.7/site-packages/dnf/base.py", line 120, in _add_repo_to_sack
    repo.load()
  File "/usr/lib/python2.7/site-packages/dnf/repo.py", line 548, in load
    self._handle_load(handle)
  File "/usr/lib/python2.7/site-packages/dnf/repo.py", line 349, in _handle_load
    self._md_pload.start(self.name)
  File "/usr/lib/python2.7/site-packages/dnf/repo.py", line 312, in start
    self.progress.start(1, 1)
AttributeError: 'NoneType' object has no attribute 'start'

Local variables in innermost frame:
text: u'Russian Fedora for Fedora 20 - Nonfree'
self: <dnf.repo.MDPayload object at 0x9faa38c>

Potential duplicate: bug 1069996