X.Org random crashes on Ubuntu 15.10

[Юрий Чудновский]

Sometimes, since my upgrade to 15.10, my Xorg crashes and restart itself.
I can find this on my Xorg logs:
[171741.030] (EE)
Fatal server error:
[171741.064] (EE) TouchListenerGone: couldn't allocate events
[171741.064] (EE)
[171741.064] (EE)
Please consult the The X.Org Foundation support
  at http://wiki.x.org
 for help.
[171741.064] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[171741.064] (EE)
[171741.084] (II) AIGLX: Suspending AIGLX clients for VT switch
[171741.186] (EE) Server terminated with error (1). Closing log file.

And my display hardware is:
        *-display
             description: VGA compatible controller
             produit: Xeon E3-1200 v3/4th Gen Core Processor Integrated Graphics Controller
             fabriquant: Intel Corporation
             identifiant matériel: 2
             information bus: pci@0000:00:02.0
             version: 06
             bits: 64 bits
             horloge: 33MHz
             fonctionnalités: vga_controller bus_master cap_list rom
             configuration: driver=i915 latency=0
             ressources: irq:27 mémoire:f7800000-f7bfffff mémoire:e0000000-efffffff portE/S:f000(taille=64)

Also bug catches on HP ProBook 4320s, Intel Corporation Core Processor Integrated Graphics Controller (rev 02), Kernel driver in use: i915

[Юрий Чудновский (fqc)]

Created attachment 119298
Xorg log

After upgrading from Ubuntu 15.04 to 15.10 graphical system works visually slower and sandomly X server crashes giving error:

[ 23266.388] (EE)
Fatal server error:
[ 23266.394] (EE) TouchListenerGone: couldn't allocate events
[ 23266.394] (EE)
[ 23266.394] (EE)
Please consult the The X.Org Foundation support
         at http://wiki.x.org
 for help.
[ 23266.411] (EE) Please also check the log file at "/var/log/Xorg.0.log" for additional information.
[ 23266.411] (EE)
[ 23266.467] (II) AIGLX: Suspending AIGLX clients for VT switch
[ 23266.497] (EE) Server terminated with error (1). Closing log file.

Probably caused by i915 driver. Two systems currently known to be affected by this bug:
a) desktop on Intel Xeon E3-1200 v3/4th
b) notebook on Intel Core i3 CPU M380
both having integrated Intel graphic cards (into CPU's), both using i915 driver.

[Юрий Чудновский (fqc)]

Probably this crash is the same cause:

[ 69738.421] (EE) intel(0): When reporting this, please include /sys/class/drm/card0/error and the full dmesg.
[ 69738.721] (EE)
[ 69738.721] (EE) Backtrace:
[ 69738.816] (EE) 0: /usr/bin/X (xorg_backtrace+0x4e) [0x5584f565662e]
[ 69738.816] (EE) 1: /usr/bin/X (0x5584f54a2000+0x1b8999) [0x5584f565a999]
[ 69738.816] (EE) 2: /lib/x86_64-linux-gnu/libc.so.6 (0x7f4086863000+0x352f0) [0x7f40868982f0]
[ 69738.816] (EE) 3: /usr/lib/xorg/modules/drivers/intel_drv.so (0x7f4082c3a000+0x1046cb) [0x7f4082d3e6cb]
[ 69738.816] (EE) 4: /usr/lib/xorg/modules/drivers/intel_drv.so (0x7f4082c3a000+0x10749b) [0x7f4082d4149b]
[ 69738.816] (EE) 5: /usr/bin/X (DRI2SwapBuffers+0x1c8) [0x5584f5628cf8]
[ 69738.816] (EE) 6: /usr/bin/X (0x5584f54a2000+0x18867c) [0x5584f562a67c]
[ 69738.816] (EE) 7: /usr/bin/X (0x5584f54a2000+0x5818f) [0x5584f54fa18f]
[ 69738.816] (EE) 8: /usr/bin/X (0x5584f54a2000+0x5c34b) [0x5584f54fe34b]
[ 69738.817] (EE) 9: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xf0) [0x7f4086883a40]
[ 69738.817] (EE) 10: /usr/bin/X (_start+0x29) [0x5584f54e86c9]
[ 69738.817] (EE)
[ 69738.817] (EE) Segmentation fault at address 0x10
[ 69738.817] (EE)
Fatal server error:
[ 69738.817] (EE) Caught signal 11 (Segmentation fault). Server aborting

Maybe not. /sys/class/drm/card0/error contain "no error state collected" and dmesg give me nothing interesting.

[Юрий Чудновский (fqc)]

More automatically collected by Apport system info can be inspected here: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1511819

[Launchpad Janitor (janitor)]

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

[Chris Wilson (ickle)]

I presume mea culpa,

commit 2d26643cab33a32847afaf13b50d326d09d58bf7
Author: Chris Wilson <email address hidden>
Date: Fri Nov 13 19:03:36 2015 +0000

    sna/dri2: Drop the reference on the fence when complet

[Юрий Чудновский (fqc)]

Workaround found, see here: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1510970
Bur reported to be fixed on X.org bugtracker: https://bugs.freedesktop.org/show_bug.cgi?id=92735