Description of problem:
The following was filed automatically by anaconda:
anaconda 19.30-1 exception report
Traceback (most recent call first):
  File "/usr/lib/python2.7/site-packages/blivet/formats/fs.py", line 626, in unmount
    raise FSError("umount failed")
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 4018, in _undo_temp_mount
    fmt.unmount()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 4164, in listSubVolumes
    self._undo_temp_mount()
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1540, in handleBTRFSFormat
    for subvol_dict in btrfs_dev.listSubVolumes():
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1662, in handleUdevDeviceFormat
    self.handleBTRFSFormat(info, device)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1077, in addUdevDevice
    self.handleUdevDeviceFormat(info, device)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1874, in _populate
    self.addUdevDevice(dev)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1818, in populate
    self._populate()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 409, in reset
    self.devicetree.populate(cleanupOnly=cleanupOnly)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 140, in storageInitialize
    storage.reset()
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 168, in run
    threading.Thread.run(self, *args, **kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 87, in wait
    self.raise_error(name)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/packaging/__init__.py", line 657, in payloadInitialize
    threadMgr.wait(THREAD_STORAGE)
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 168, in run
    threading.Thread.run(self, *args, **kwargs)
FSError: umount failed

Version-Release number of selected component:
anaconda-19.30-1

Additional info:
reporter:       libreport-2.1.4
cmdline:        /usr/bin/python  /sbin/anaconda
cmdline_file:   initrd=initrd.img inst.stage2=hd:LABEL=Fedora\x2019-Beta\x20x86_64 quiet BOOT_IMAGE=vmlinuz 
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         3.9.2-301.fc19.x86_64
product:        Fedora
release:        Cannot get release name.
type:           anaconda
version:        19-Beta

Truncated backtrace:
Traceback (most recent call last):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 168, in run
    threading.Thread.run(self, *args, **kwargs)
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/packaging/__init__.py", line 657, in payloadInitialize
    threadMgr.wait(THREAD_STORAGE)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 87, in wait
    self.raise_error(name)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 168, in run
    threading.Thread.run(self, *args, **kwargs)
  File "/usr/lib64/python2.7/threading.py", line 766, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 140, in storageInitialize
    storage.reset()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 409, in reset
    self.devicetree.populate(cleanupOnly=cleanupOnly)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1818, in populate
    self._populate()
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1874, in _populate
    self.addUdevDevice(dev)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1077, in addUdevDevice
    self.handleUdevDeviceFormat(info, device)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1662, in handleUdevDeviceFormat
    self.handleBTRFSFormat(info, device)
  File "/usr/lib/python2.7/site-packages/blivet/devicetree.py", line 1540, in handleBTRFSFormat
    for subvol_dict in btrfs_dev.listSubVolumes():
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 4164, in listSubVolumes
    self._undo_temp_mount()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 4018, in _undo_temp_mount
    fmt.unmount()
  File "/usr/lib/python2.7/site-packages/blivet/formats/fs.py", line 626, in unmount
    raise FSError("umount failed")
FSError: umount failed