Description of problem:
Yesterday I was helping a student with F21 installation. He had a completely full disk (Windows installation, 4 partitions, allegedly as provided by manufacturer and untouched), but anaconda displayed it a completely empty! That means the partition spoke overview, and also custom partition spoke - no existing partitions were shown.

That's a serious problem, because not only it would not be able to install alongside Windows, it would probably erase the disk contents completely, destroying all previous data.

I collected all the logs and hope it will help you debug the issue. I looked at the disk contents in several applications. gnome-disks showed the disk contents without any problems. gparted worked as well, but reported some warnings and errors (but honestly, I always see some warnings from gparted, so that doesn't need to mean much).

Version-Release number of selected component (if applicable):
F21 Alpha Workstation x86_64 Live
anaconda-21.48.6-1.fc21.x86_64
python-blivet-0.62-1.fc21.noarch

How reproducible:
always, for *that particular disk*

Steps to Reproduce:
1. check existing boot contents - boot windows (ok), display partitions in gnome-disks (ok)
2. run installer
3. see that anaconda reports roughly 590GB disk with 590GB free space, i.e. completely empty disk

Actual results:
the disk is reported as empty

Expected results:
the disk should be reported as full

Additional info:
F20 anaconda exhibited the same problem. Originally I wanted to install F20, then tried F21, the same problem.