Description of problem:
Tried to install Fedora 20 from live ISO.  Chose custom partitioning.  The target disks were already luks+LVM.  I do not know whether the installer planned to keep the luks or overwrite it; I did not see any luks options.  I had mounted the target disks in the live session using the file manager to examine them.  The installer did not ask me for luks passwords.

Version-Release number of selected component:
anaconda-20.25.15-1.fc20.x86_64

The following was filed automatically by anaconda:
anaconda 20.25.15-1 exception report
Traceback (most recent call first):
  File "/usr/lib/python2.7/site-packages/blivet/formats/luks.py", line 162, in setup
    raise LUKSError("luks device not configured")
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 839, in setupParents
    _format.setup()
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 702, in _preSetup
    self.setupParents(orig=orig)
  File "/usr/lib/python2.7/site-packages/blivet/devices.py", line 713, in setup
    if not self._preSetup(orig=orig):
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 2659, in turnOnSwap
    device.setup()
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 1679, in turnOnSwap
    upgrading=upgrading)
  File "/usr/lib/python2.7/site-packages/blivet/__init__.py", line 179, in turnOnFilesystems
    storage.turnOnSwap()
  File "/usr/lib64/python2.7/site-packages/pyanaconda/install.py", line 142, in doInstall
    turnOnFilesystems(storage, mountOnly=flags.flags.dirInstall)
  File "/usr/lib64/python2.7/threading.py", line 764, in run
    self.__target(*self.__args, **self.__kwargs)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/threads.py", line 192, in run
    threading.Thread.run(self, *args, **kwargs)
LUKSError: luks device not configured

Additional info:
cmdline:        /usr/bin/python  /sbin/anaconda --liveinst --method=livecd:///dev/mapper/live-base
cmdline_file:   initrd=initrd0.img root=live:CDLABEL=Fedora-Live-Desktop-x86_64-20-1 rootfstype=auto ro rd.live.image quiet  rhgb rd.luks=0 rd.md=0 rd.dm=0  BOOT_IMAGE=vmlinuz0 
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         3.11.10-301.fc20.x86_64
other involved packages: python-blivet-0.23.9-1.fc20.noarch, python-libs-2.7.5-9.fc20.x86_64
product:        Fedora
release:        Fedora release 20 (Heisenbug)
type:           anaconda
version:        20