Bug 1814005

Description of problem:
I did custom partitioning and it gave this error

Version-Release number of selected component:
anaconda-31.22.6

The following was filed automatically by anaconda:
anaconda 31.22.6 exception report
Traceback (most recent call first):
  File "/usr/lib/python3.7/site-packages/blivet/formats/__init__.py", line 558, in _pre_destroy
    raise DeviceFormatError("device is active")
  File "/usr/lib/python3.7/site-packages/blivet/threads.py", line 53, in run_with_lock
    return m(*args, **kwargs)
  File "/usr/lib/python3.7/site-packages/blivet/formats/__init__.py", line 548, in destroy
    self._pre_destroy(**kwargs)
  File "/usr/lib/python3.7/site-packages/blivet/threads.py", line 53, in run_with_lock
    return m(*args, **kwargs)
  File "/usr/lib/python3.7/site-packages/blivet/deviceaction.py", line 723, in execute
    self.format.destroy()
  File "/usr/lib/python3.7/site-packages/blivet/threads.py", line 53, in run_with_lock
    return m(*args, **kwargs)
  File "/usr/lib/python3.7/site-packages/blivet/actionlist.py", line 327, in process
    action.execute(callbacks)
  File "/usr/lib/python3.7/site-packages/blivet/actionlist.py", line 48, in wrapped_func
    return func(obj, *args, **kwargs)
  File "/usr/lib/python3.7/site-packages/blivet/blivet.py", line 106, in do_it
    self.devicetree.actions.process(callbacks=callbacks, devices=self.devices)
  File "/usr/lib/python3.7/site-packages/blivet/threads.py", line 53, in run_with_lock
    return m(*args, **kwargs)
  File "/usr/lib64/python3.7/site-packages/pyanaconda/storage/installation.py", line 50, in turn_on_filesystems
    storage.do_it(callbacks)
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation_tasks.py", line 450, in run_task
    self._task(*self._task_args, **self._task_kwargs)
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation_tasks.py", line 484, in start
    self.run_task()
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation_tasks.py", line 305, in start
    item.start()
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation_tasks.py", line 305, in start
    item.start()
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation_tasks.py", line 305, in start
    item.start()
  File "/usr/lib64/python3.7/site-packages/pyanaconda/installation.py", line 394, in run_installation
    queue.start()
  File "/usr/lib64/python3.7/threading.py", line 870, in run
    self._target(*self._args, **self._kwargs)
  File "/usr/lib64/python3.7/site-packages/pyanaconda/threading.py", line 280, in run
    threading.Thread.run(self)
blivet.errors.DeviceFormatError: device is active

Additional info:
addons:         com_redhat_kdump
cmdline:        /usr/bin/python3  /sbin/anaconda
cmdline_file:   BOOT_IMAGE=vmlinuz initrd=initrd.img inst.stage2=hd:LABEL=Fedora-S-dvd-x86_64-31 rd.live.check quiet
dnf.librepo.log: 
executable:     /sbin/anaconda
hashmarkername: anaconda
hawkey.log:     INFO mar-16 17:51:23 === Started libdnf-0.35.3 ===
kernel:         5.3.7-301.fc31.x86_64
product:        Fedora
release:        Fedora release 31 (Thirty One)
type:           anaconda
version:        31