unity8 assert failure: *** Error in `unity8': double free or corruption (fasttop): 0xb20055a0 ***

[Alberto Mardegan]

Starting the unity8-desktop-session-mir in a Lenovo IdeaPad s3-10t. I get a black screen, with a mouse cursor. unity8 is not running.

ProblemType: Crash
DistroRelease: Ubuntu 15.04
Package: unity8 8.02+15.04.20150123.3-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-45.74-generic 3.13.11-ckt13
Uname: Linux 3.13.0-45-generic i686
ApportVersion: 2.15.1-0ubuntu4
Architecture: i386
AssertionMessage: *** Error in `unity8': double free or corruption (fasttop): 0xb20055a0 ***
CrashCounter: 1
Date: Thu Feb 5 11:20:30 2015
ExecutablePath: /usr/bin/unity8
InstallationDate: Installed on 2012-10-07 (850 days ago)
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release i386 (20120817.3)
ProcCmdline: unity8
ProcEnviron:
 LANGUAGE=en_US
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 SHELL=/bin/bash
Signal: 6
SourcePackage: unity8
StacktraceTop:
 __libc_message (do_abort=do_abort@entry=1, fmt=fmt@entry=0xb616a89c "*** Error in `%s': %s: 0x%s ***\n") at ../sysdeps/posix/libc_fatal.c:175
 malloc_printerr (action=<optimized out>, str=0xb616aa60 "double free or corruption (fasttop)", ptr=0xb20055a0) at malloc.c:4996
 _int_free (av=0xb2000010, p=<optimized out>, have_lock=0) at malloc.c:3840
 ?? () from /usr/lib/i386-linux-gnu/libgbm.so.1
 gbm_device_destroy () from /usr/lib/i386-linux-gnu/libgbm.so.1
Title: unity8 assert failure: *** Error in `unity8': double free or corruption (fasttop): 0xb20055a0 ***
UpgradeStatus: Upgraded to vivid on 2015-01-31 (4 days ago)
UserGroups: adm lpadmin nopasswdlogin sambashare sudo
upstart.unity8.log:
 ()
 [1423128879.172108] (II) SharedLibrary: Loading libmirplatform5driver.so
 qtmir.mir: MirServer created
 [1423128879.540845] (II) Server: Starting
 *** Error in `unity8': double free or corruption (fasttop): 0xb20055a0 ***

[Apport retracing service (apport)]

StacktraceTop:
 __libc_message (do_abort=do_abort@entry=1, fmt=fmt@entry=0xb616a89c "*** Error in `%s': %s: 0x%s ***\n") at ../sysdeps/posix/libc_fatal.c:175
 malloc_printerr (action=<optimized out>, str=0xb616aa60 "double free or corruption (fasttop)", ptr=0xb20055a0) at malloc.c:4996
 _int_free (av=0xb2000010, p=<optimized out>, have_lock=0) at malloc.c:3840
 __GI___libc_free (mem=<optimized out>) at malloc.c:2946
 dri_destroy (gbm=0xb2005a18) at ../../../../src/gbm/backends/dri/gbm_dri.c:938

[Alberto Mardegan (mardy)]

Attached the strace file from the command:

DESKTOP_SESSION=unity8-mir MIR_SOCKET=$XDG_RUNTIME_DIR/mir_socket MIR_SERVER_PROMPT_FILE=1 MIR_SERVER_HOST_SOCKET=/run/lightdm-mir-0 MIR_SERVER_FILE=$XDG_RUNTIME_DIR/mir_socket MIR_SERVER_NAME=session-0 UNITY_INDICATOR_PROFILE=desktop QT_QPA_PLATFORM=mirserver strace /usr/bin/unity8 2> unity8-strace.log

[Alberto Mardegan (mardy)]

Adding a valgrind of a qmlscene with a simple rectangle, with the same environment as before.

[Launchpad Janitor (janitor)]

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

[Alexandros Frantzis (afrantzis)]

The "double free or corruption" part of this problem is bug 1414999.

The core issue causing the failure is a failure to create an EGLContext with the specificied attributes, probably a duplicate of bug 1408910.

[kevin gunn (kgunn72)]

OK - based on the comment above & digging thru those bug trails, with those 2 bugs being closed now, can you please retest to see if this is still occuring. the latest Mesa in vivid should address this

[Alberto Mardegan (mardy)]

Yes, indeed this is now fixed. The ideapad now shows the unity8 UI, though it looks like no apps starting. But the indicators work, meaning that this bug is fixed.