Xorg assert failure: Xorg: ../../../../dix/privates.c:384: dixRegisterPrivateKey: Assertion `!global_keys[type].created' failed.

[Joe]

Ubuntu running as a VMPlayer 15.5 (Win10) client freezes at Xorg GUI start.
boot parameter nomodeset avoids the problem, but then the resolution is limited and cannot be set to host full screen 2560 x 1440 anymore.

ProblemType: Crash
DistroRelease: Ubuntu 18.04
Package: xserver-xorg-core-hwe-18.04 2:1.20.4-1ubuntu3~18.04.1
ProcVersionSignature: Ubuntu 5.0.0-29.31~18.04.1-generic 5.0.21
Uname: Linux 5.0.0-29-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.7
Architecture: amd64
AssertionMessage: Xorg: ../../../../dix/privates.c:384: dixRegisterPrivateKey: Assertion `!global_keys[type].created' failed.
CrashCounter: 1
Date: Thu Oct 3 22:48:34 2019
ExecutablePath: /usr/lib/xorg/Xorg
InstallationDate: Installed on 2019-02-19 (225 days ago)
InstallationMedia: Ubuntu 18.04.2 LTS "Bionic Beaver" - Release amd64 (20190210)
ProcCmdline: /usr/lib/xorg/Xorg vt1 -displayfd 3 -auth /run/user/121/gdm/Xauthority -background none -noreset -keeptty -verbose 3
ProcEnviron:

Signal: 6
SourcePackage: xorg-server-hwe-18.04
StacktraceTop:
 __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:51
 __GI_abort () at abort.c:79
 __assert_fail_base (fmt=0x7f0eea4777d8 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x5652a22f699d "!global_keys[type].created", file=file@entry=0x5652a22f6958 "../../../../dix/privates.c", line=line@entry=384, function=function@entry=0x5652a22f6c00 "dixRegisterPrivateKey") at assert.c:92
 __GI___assert_fail (assertion=0x5652a22f699d "!global_keys[type].created", file=0x5652a22f6958 "../../../../dix/privates.c", line=384, function=0x5652a22f6c00 "dixRegisterPrivateKey") at assert.c:101
 dixRegisterPrivateKey ()
Title: Xorg assert failure: Xorg: ../../../../dix/privates.c:384: dixRegisterPrivateKey: Assertion `!global_keys[type].created' failed.
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Apport retracing service (apport)]

StacktraceSource:
 #0 0x00007f0eea2fee97 in ?? ()
 #1 0x000000000a392000 in ?? ()
 #2 0x0000000000000000 in ?? ()
StacktraceTop:
 ?? ()
 ?? ()
 ?? ()

[Joe (joehtg)]

I have now restored the VM-image with Linux 4.18.0-24-generic #25~18.04.1-Ubuntu - no crash anymore.
Seems that the unattended upgrade to Linux 5.0.0-29-generic introduced the crash. Might be bug #1792932.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.