Xorg crashed with SIGABRT in has_offload_slaves()

[mkis62]

crashed closing Software Center...

ProblemType: Crash
DistroRelease: Ubuntu 13.10
Package: xserver-xorg-core 2:1.14.2-0ubuntu8
ProcVersionSignature: Ubuntu 3.11.0-0.2-generic 3.11.0-rc4
Uname: Linux 3.11.0-0-generic i686
ApportVersion: 2.12-0ubuntu3
Architecture: i386
CrashCounter: 1
Date: Tue Aug 6 14:24:16 2013
ExecutablePath: /usr/bin/Xorg
InstallationDate: Installed on 2013-06-12 (55 days ago)
InstallationMedia: Xubuntu 13.10 "Saucy Salamander" - Alpha i386 (20130611)
MarkForUpload: True
ProcCmdline: /usr/bin/X -core :0 -auth /var/run/lightdm/root/:0 -nolisten tcp vt7 -novtswitch
ProcEnviron:

Signal: 6
SourcePackage: xorg-server
StacktraceTop:
 ?? () from /usr/lib/xorg/modules/drivers/intel_drv.so
 ?? () from /usr/lib/xorg/modules/drivers/intel_drv.so
 ?? () from /usr/lib/xorg/modules/drivers/intel_drv.so
 BlockHandler ()
 WaitForSomething ()
Title: Xorg crashed with SIGABRT in BlockHandler()
UpgradeStatus: No upgrade log present (probably fresh install)
UserGroups:

[Apport retracing service (apport)]

StacktraceTop:
 has_offload_slaves (sna=<optimized out>) at ../../../src/sna/sna_accel.c:14688
 stop_flush (scanout=0xb96bb060, sna=0xb5cea000) at ../../../src/sna/sna_accel.c:14751
 sna_accel_flush (sna=0xb5cea000) at ../../../src/sna/sna_accel.c:14973
 sna_accel_block_handler (sna=sna@entry=0xb5cea000, tv=tv@entry=0xbfc051f4) at ../../../src/sna/sna_accel.c:15413
 sna_block_handler (arg=0xb967f988, timeout=0xbfc051f4, read_mask=0xb7726a80 <LastSelectMask>) at ../../../src/sna/sna_driver.c:568