+++ This bug was initially created as a clone of Bug #1024144 +++

Description of problem:
Tried to add a 25gb root thinp LV to existing thinpool, all existing and the new installation listing on the left vanished (totally blank space) and about a minute later a crash.

Version-Release number of selected component:
anaconda-20.25.4-1

The following was filed automatically by anaconda:
anaconda 20.25.4-1 exception report
Traceback (most recent call first):
  File "/tmp/updates/blivet/size.py", line 88, in _parseSpec
    raise SizeNotPositiveError("spec= param must be >=0")
  File "/tmp/updates/blivet/size.py", line 138, in __new__
    self = Decimal.__new__(cls, value=_parseSpec(spec))
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/lib/accordion.py", line 61, in selectorFromDevice
    size = Size(spec="%f MB" % device.size)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/lib/accordion.py", line 176, in addSelector
    selector = selectorFromDevice(device, mountpoint=mountpoint)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/custom.py", line 989, in _do_refresh
    mountpoint=mountpoint)
  File "/usr/lib64/python2.7/site-packages/pyanaconda/ui/gui/spokes/custom.py", line 2064, in on_add_clicked
    self._do_refresh(mountpointToShow=mountpoint or fstype)
SizeNotPositiveError: spec= param must be >=0

Additional info:
cmdline:        /usr/bin/python  /sbin/anaconda
cmdline_file:   initrd=initrd.img inst.stage2=hd:LABEL=Fedora\x2020-Beta-TC6\x20x86_64 quiet elevator=noop updates=http://dlehman.fedorapeople.org/updates/updates-1024076.0.img BOOT_IMAGE=vmlinuz 
executable:     /sbin/anaconda
hashmarkername: anaconda
kernel:         3.11.6-301.fc20.x86_64
product:        Fedora
release:        Cannot get release name.
type:           anaconda
version:        20-Beta-TC6

--- Additional comment from Chris Murphy on 2013-10-31 00:16:59 EDT ---

Oh great, as it turns out I did alter the LVM layout outside of the installer, and overcommitted it by 250GB afterall. I may have been suitably punished by spending hours trying to reproduce this bug thinking I hadn't until I read the logs. *sigh*

To reproduce the crash, via thinp overcommitting outside the installer I have these steps.

1. Install to a new clean disk using LVM Thin Provisioning partition scheme via the guided partitioning path.

2. Reboot to the installed system and create a new vLV, format it ext4.
lvcreate --thinpool fedora/pool00 --virtualsize 250g -n punishment

3. Reboot to the installer, applying updates.img, set partition scheme again to LVM thinp, go to custom partitioning.

4. Add new mount point /, at 25gb.

Result:
Installer says "Added new LVM Thin Provisioning to existing container fedora." And crashes about 15 seconds later. No warnings, error messages, or corrections to the 25GB entry I put in.

--- Additional comment from David Lehman on 2013-11-06 09:46:40 EST ---

This bug is about anaconda/blivet not handling the case of a preexisting overcommitted thin pool. I have patches that have resolved the issue in my testing.