A frozen screen is most likely the unity8 process crashing rather than hanging. When this happens, unity-system-compositor will just display the latest frame from unity8 so it appears to be frozen.
I can't tell from the attached log which unity8 crash you are encountering. So we need more information but I don't know where from... ** Changed in: unity8 (Ubuntu) Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to unity8 in Ubuntu. https://bugs.launchpad.net/bugs/1663256 Title: cannot login to unity 8 - mouse and loading starting screen freeze Status in unity8 package in Ubuntu: Incomplete Bug description: When I log into unity 8 session first i see black screen and next is wallpeper with left and top dash and loading starting scope with apps but no apps show up just freezes everything. Mouse and keyboard is not working. When I log in to unity 7 everthing is fine. Where is the problem? ProblemType: Bug DistroRelease: Ubuntu 17.04 Package: unity8 8.15+17.04.20170131.1-0ubuntu1 ProcVersionSignature: Ubuntu 4.9.0-15.16-generic 4.9.5 Uname: Linux 4.9.0-15-generic x86_64 ApportVersion: 2.20.4-0ubuntu1 Architecture: amd64 CurrentDesktop: Unity Date: Thu Feb 9 15:52:20 2017 InstallationDate: Installed on 2017-01-28 (12 days ago) InstallationMedia: Ubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.2) SourcePackage: unity8 UpgradeStatus: Upgraded to zesty on 2017-02-09 (0 days ago) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/unity8/+bug/1663256/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp