Created attachment 330566 [details]
Fix crash with incomplete VGs

Description of problem:

I plugged in a disk which happened to be part of a LVM volume group and ran anaconda. When setting up LVM, it would not let me use the name of the old VG and crashed after I finished partitioning.

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

Today's rawhide.

How reproducible:

With partial VGs present.

Steps to Reproduce:
1. Setup LVM across two disks
2. Erase one of the disks
3. Run anaconda

Actual results:

1.) Can't choose the name of VG equal to the old VG name.
2.) Unhandled exception after partitioning is done:

anaconda 11.5.0.12 exception report
Traceback (most recent call first):
  File "/usr/lib/anaconda/lvm.py", line 282, in vgremove
    raise VGRemoveError, vgname
  File "/usr/lib/anaconda/partitions.py", line 1787, in doMetaDeletes
    lvm.vgremove(delete.name)
  File "/usr/lib/anaconda/packages.py", line 136, in turnOnFilesystems
    anaconda.id.partitions.doMetaDeletes(anaconda.id.diskset)
  File "/usr/lib/anaconda/dispatch.py", line 204, in moveStep
    rc = stepFunc(self.anaconda)
  File "/usr/lib/anaconda/dispatch.py", line 127, in gotoNext
    self.moveStep()
  File "/usr/lib/anaconda/gui.py", line 1358, in nextClicked
    self.anaconda.dispatch.gotoNext()
VGRemoveError: vgremove of vg "VolGroup00" failed
Log:
   Using volume group(s) on command line
   Finding volume group "VolGroup00"
   Wiping cache of LVM-capable devices
   Couldn't find device with uuid 'LGr24v-fkhw-00GZ-kdYc-2rfn-x8mC-Caw9Lm'.
   There are 1 physical volumes missing.
   Volume group "VolGroup00" not found, is inconsistent or has PVs missing.
   Consider vgreduce --removemissing if metadata is inconsistent.

Local variables in innermost frame:
pvs: ['/dev/sda2', 'unknown device']
args: ['vgremove', '-v', 'VolGroup00']
pv: ('unknown device', 'VolGroup00', 0L)
vgname: VolGroup00
rc: 5

Expected results:

Disk partitioned properly.

Additional info:

Attached patch. Tested.