Held package libgm1 after upgrade from Trusty to Wily

[John Rose]

I've upgraded from Trusty to Wily (via Vivid, if I remember correctly). Afterwards 'apt-get upgrade' shows libgbm1 (& xorg) as kept back & not to upgrade. Synaptic shows libgbm1-lts-vivid as installed. Not really sure if this is a bug.
PS Not sure if this is connected, but I'm not able to install Skype using 'apt-get install skype skype-bin:i386':
The following packages have unmet dependencies.
 skype-bin:i386 : Depends: libqtwebkit4:i386 (>= 2.2~2011week36) but it is not going to be installed
                  Depends: libgl1-mesa-glx:i386 but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: libgbm1 10.1.3-0ubuntu0.5
Uname: Linux 4.0.0-040000-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.19.1-0ubuntu5
Architecture: amd64
CompizPlugins: No value set for `/apps/compiz-1/general/screen0/options/active_plugins'
CompositorRunning: compiz
CompositorUnredirectDriverBlacklist: '(nouveau|Intel).*Mesa 8.0'
CompositorUnredirectFSW: true
CurrentDesktop: Unity
Date: Fri Dec 18 18:19:58 2015
DistUpgraded: 2015-12-18 15:46:31,219 DEBUG enabling apt cron job
DistroCodename: wily
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Device [8086:22b1] (rev 21) (prog-if 00 [VGA controller])
   Subsystem: Intel Corporation Device [8086:2060]
InstallationDate: Installed on 2015-11-26 (22 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.0.0-040000-generic root=UUID=e6a0e473-929d-4492-bce9-080a2ff09077 ro quiet splash vt.handoff=7
SourcePackage: mesa
UpgradeStatus: Upgraded to wily on 2015-12-18 (0 days ago)
dmi.bios.date: 09/04/2015
dmi.bios.vendor: Intel Corp.
dmi.bios.version: PYBSWCEL.86A.0043.2015.0904.1904
dmi.board.name: NUC5CPYB
dmi.board.vendor: Intel Corporation
dmi.board.version: H61145-404
dmi.chassis.type: 3
dmi.modalias: dmi:bvnIntelCorp.:bvrPYBSWCEL.86A.0043.2015.0904.1904:bd09/04/2015:svn:pn:pvr:rvnIntelCorporation:rnNUC5CPYB:rvrH61145-404:cvn:ct3:cvr:
version.compiz: compiz 1:0.9.12.2+15.10.20151015-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.64-1
version.libgl1-mesa-dri: libgl1-mesa-dri N/A
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx N/A
version.xserver-xorg-core: xserver-xorg-core N/A
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev N/A
version.xserver-xorg-video-ati: xserver-xorg-video-ati N/A
version.xserver-xorg-video-intel: xserver-xorg-video-intel N/A
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau N/A
xserver.bootTime: Fri Dec 18 17:13:33 2015
xserver.configfile: default
xserver.errors:

xserver.logfile: /var/log/Xorg.0.log
xserver.outputs:

xserver.version: 2:1.17.1-0ubuntu3.1~trusty1

[Timo Aaltonen (tjaalton)]

upgrades like that are not supported, you need to revert back to stock trusty packages first (from lts-vivid)