Description of problem:
We are trying to write kickstart file which will allow to reinstall a machine
keeping /home partition which are encrypted.

Version-Release number of selected component (if applicable):
anaconda 21.48.21-1

How reproducible:
Always

Steps to Reproduce:
1. Define a kickstart with manual partitioning to be able to keep existing encrypted /home partition:
...
logvol /home  --fstype="ext4" --noformat --useexisting --encrypted --passphrase=xxxx --name=home --vgname=fedora-server_xxxx
...
2. Launch an install with this kickstart file
3.

Actual results:
Anaconda installation ends with an exception:
anaconda 21.48.21-1 exception report
Traceback (most recent call first):
  File "/usr/lib64/python2.7/site-packages/pyanaconda/kickstart.py", line 1029, in execute
    min_luks_entropy=MIN_CREATE_ENTROPY)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/kickstart.py", line 803, in execute
    l.execute(storage, ksdata, instClass)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/kickstart.py", line 2013, in doKickstartStorage
    ksdata.logvol.execute(storage, ksdata, instClass)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/storage.py", line 313, in _doExecute
    doKickstartStorage(self.storage, self.data, self.instclass)
  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 227, in run
    threading.Thread.run(self, *args, **kwargs)
TypeError: __init__() got an unexpected keyword argument 'min_luks_entropy'

Expected results:


Additional info:
Looking at anaconda sources (kickstart.py line 1029 in F21-branch), we can see that a "min_luks_entropy" argument is used to create a LUKSDevice instance.
Problem is that this argument is unexpected for a LUKSDevice.
I think that this argument should have been used in the previous "getFormat" call and therefore the code should be:
...
            if self.preexist:
                luksformat = fmt
                device.format = getFormat("luks", passphrase=self.passphrase, device=device.path,
                                          cipher=self.cipher,
                                          escrow_cert=cert,
                                          add_backup_passphrase=self.backuppassphrase,
                                          min_luks_entropy=MIN_CREATE_ENTROPY)
                luksdev = LUKSDevice("luks%d" % storage.nextID,
                                     fmt=luksformat,
                                     parents=device)
...