Upgrade to 15.04 crashes

[luigi1015]

Just as the summary suggests, I'm trying to upgrade to 15.04 and it crashes. I've been upgrading this same system since at least 13.04 and haven't had this problem until now. I'm not running a pre-release version of Ubuntu. I think debug info is being added automatically.

Here's the text of the window that pops up:
Could not calculate the upgrade

An unresolvable problem occurred while calculating the upgrade.

 This can be caused by:
 * Upgrading to a pre-release version of Ubuntu
 * Running the current pre-release version of Ubuntu
 * Unofficial software packages not provided by Ubuntu

If none of this applies, then please report this bug using the command 'ubuntu-bug ubuntu-release-upgrader-core' in a terminal.

ProblemType: Bug
DistroRelease: Ubuntu 14.10
Package: ubuntu-release-upgrader-core 1:14.10.10
ProcVersionSignature: Ubuntu 3.16.0-37.51-generic 3.16.7-ckt9
Uname: Linux 3.16.0-37-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.7-0ubuntu8.4
Architecture: amd64
CrashDB: ubuntu
CurrentDesktop: Unity
Date: Tue May 19 07:17:23 2015
EcryptfsInUse: Yes
InstallationDate: Installed on 2013-01-05 (864 days ago)
InstallationMedia: Ubuntu 12.10 "Quantal Quetzal" - Release amd64 (20121017.5)
PackageArchitecture: all
SourcePackage: ubuntu-release-upgrader
UpgradeStatus: Upgraded to utopic on 2015-05-19 (0 days ago)
VarLogDistupgradeTermlog:

[Brian Murray (brian-murray)]

From Aptlog.txt:

Investigating (9) libhwloc5 [ amd64 ] < 1.8-1ubuntu1.14.10.1 -> 1.10.0-3 > ( universe/libs )
Broken libhwloc5:amd64 Breaks on libhwloc-plugins [ amd64 ] < 1.8-1ubuntu1 -> 1.10.0-3 > ( universe/libs ) (< 1.10~)
  Considering libhwloc-plugins:amd64 0 as a solution to libhwloc5:amd64 5
  Upgrading libhwloc-plugins:amd64 due to Breaks field in libhwloc5:amd64
Investigating (9) libhwloc-plugins [ amd64 ] < 1.8-1ubuntu1 -> 1.10.0-3 > ( universe/libs )
Broken libhwloc-plugins:amd64 Depends on ocl-icd-libopencl1 [ amd64 ] < none -> 2.2.3-1 > ( libs ) (>= 1.0)
  Considering ocl-icd-libopencl1:amd64 1 as a solution to libhwloc-plugins:amd64 0
  MarkKeep libhwloc-plugins [ amd64 ] < 1.8-1ubuntu1 -> 1.10.0-3 > ( universe/libs ) FU=0
  Holding Back libhwloc-plugins:amd64 rather than change ocl-icd-libopencl1:amd64
Broken libhwloc-plugins:amd64 Depends on libopencl-1.1-1 [ amd64 ] < none > ( none )
  Considering ocl-icd-libopencl1:amd64 1 as a solution to libhwloc-plugins:amd64 0
  MarkKeep libhwloc-plugins [ amd64 ] < 1.8-1ubuntu1 -> 1.10.0-3 > ( universe/libs ) FU=0
  Holding Back libhwloc-plugins:amd64 rather than change libopencl-1.1-1:amd64
  Or group keep for libhwloc-plugins:amd64
  MarkKeep libhwloc-plugins [ amd64 ] < 1.8-1ubuntu1 -> 1.10.0-3 > ( universe/libs ) FU=0
Done