[    49.615] (II) config/udev: Adding input device ImPS/2 Generic Wheel Mouse (/dev/input/mouse0)
[    49.622] (II) No input driver specified, ignoring this device.
[    49.622] (II) This device may have been added with another device file.
[    58.448] (II) XKB: reuse xkmfile /var/lib/xkb/server-03AF3717FF3AB439A4BAABA686CCB40771CDF520.xkm
[  1637.173] [mi] EQ overflowing.  Additional events will be discarded until existing events are processed.
[  1637.544] 
Backtrace:
[  1638.821] 0: /usr/bin/X (xorg_backtrace+0x37) [0xe67637]
[  1638.821] 1: /usr/bin/X (mieqEnqueue+0x223) [0xe45983]
[  1638.821] 2: /usr/bin/X (0xcdf000+0x4cc35) [0xd2bc35]
[  1638.821] 3: /usr/bin/X (xf86PostMotionEventM+0xf9) [0xd6cda9]
[  1638.821] 4: /usr/lib/xorg/modules/input/evdev_drv.so (0x3de000+0x3c3d) [0x3e1c3d]
[  1638.821] 5: /usr/lib/xorg/modules/input/evdev_drv.so (0x3de000+0x524f) [0x3e324f]
[  1638.836] 6: /usr/bin/X (0xcdf000+0x782c1) [0xd572c1]
[  1638.836] 7: /usr/bin/X (0xcdf000+0x9fcf8) [0xd7ecf8]
[  1638.836] 8: (vdso) (__kernel_sigreturn+0x0) [0x787400]
[  1638.836] 9: /usr/bin/X (0xcdf000+0x18c8d0) [0xe6b8d0]
[  1638.836] 10: (vdso) (__kernel_sigreturn+0x0) [0x787400]
[  1638.836] 11: /usr/bin/X (0xcdf000+0x110630) [0xdef630]
[  1638.836] 12: /usr/bin/X (0xcdf000+0xdcd29) [0xdbbd29]
[  1638.836] 13: /usr/bin/X (0xcdf000+0xde22f) [0xdbd22f]
[  1638.836] 14: /usr/bin/X (0xcdf000+0x3787d) [0xd1687d]
[  1638.836] 15: /usr/bin/X (0xcdf000+0x252aa) [0xd042aa]
[  1638.836] 16: /lib/i386-linux-gnu/libc.so.6 (__libc_start_main+0xf3) [0x5254d3]
[  1638.836] 17: /usr/bin/X (0xcdf000+0x255e9) [0xd045e9]
[  1638.836] [mi] These backtraces from mieqEnqueue may point to a culprit higher up the stack.
[  1638.836] [mi] mieq is *NOT* the cause.  It is a victim.
[  1638.837] [mi] Increasing EQ size to 512 to prevent dropped events.
[  1638.837] [mi] EQ processing has resumed after 41 dropped events.
[  1638.838] [mi] This may be caused my a misbehaving driver monopolizing the server's resources.

I'm using kdm with MATE desktop to avoid gdm startup sound and the unity disaster. 
From /var/log/kdm.log:

(==) Using system config directory "/usr/share/X11/xorg.conf.d"
(II) [KMS] Kernel modesetting enabled.
klauncher(1667) kdemain: No DBUS session-bus found. Check if you have started the DBUS server. 
kdeinit4: Communication error with launcher. Exiting!
kdmgreet(1386)/kdecore (K*TimeZone*): KSystemTimeZones: ktimezoned initialize() D-Bus call failed:  "Not connected to D-Bus server" 

kdmgreet(1386)/kdecore (K*TimeZone*): No time zone information obtained from ktimezoned 
[mi] EQ overflowing.  Additional events will be discarded until existing events are processed.

Backtrace:
0: /usr/bin/X (xorg_backtrace+0x37) [0xe67637]
1: /usr/bin/X (mieqEnqueue+0x223) [0xe45983]
2: /usr/bin/X (0xcdf000+0x4cc35) [0xd2bc35]
3: /usr/bin/X (xf86PostMotionEventM+0xf9) [0xd6cda9]
4: /usr/lib/xorg/modules/input/evdev_drv.so (0x3de000+0x3c3d) [0x3e1c3d]
5: /usr/lib/xorg/modules/input/evdev_drv.so (0x3de000+0x524f) [0x3e324f]
6: /usr/bin/X (0xcdf000+0x782c1) [0xd572c1]
7: /usr/bin/X (0xcdf000+0x9fcf8) [0xd7ecf8]
8: (vdso) (__kernel_sigreturn+0x0) [0x787400]
9: /usr/bin/X (0xcdf000+0x18c8d0) [0xe6b8d0]
10: (vdso) (__kernel_sigreturn+0x0) [0x787400]
11: /usr/bin/X (0xcdf000+0x110630) [0xdef630]
12: /usr/bin/X (0xcdf000+0xdcd29) [0xdbbd29]
13: /usr/bin/X (0xcdf000+0xde22f) [0xdbd22f]
14: /usr/bin/X (0xcdf000+0x3787d) [0xd1687d]
15: /usr/bin/X (0xcdf000+0x252aa) [0xd042aa]
16: /lib/i386-linux-gnu/libc.so.6 (__libc_start_main+0xf3) [0x5254d3]
17: /usr/bin/X (0xcdf000+0x255e9) [0xd045e9]
[mi] These backtraces from mieqEnqueue may point to a culprit higher up the stack.
[mi] mieq is *NOT* the cause.  It is a victim.
[mi] Increasing EQ size to 512 to prevent dropped events.
[mi] EQ processing has resumed after 41 dropped events.
[mi] This may be caused my a misbehaving driver monopolizing the server's resources.

Since last update 'gksudo  gedit' doesn't work from terminal. Also gparted-pkexec failed. Error message for gedit:
root@picipaci:~# gedit
No protocol specified

** (gedit:11591): WARNING **: A(z) „dbus-launch --autolaunch=838f708d6539fac296bb99fa4bd43890 --binary-syntax --close-stderr” parancssor nem nulla (1) állapottal lépett ki: No protocol specified\nNo protocol specified\nAutolaunch error: X11 initialization failed.\n
No protocol specified
Nem nyitható meg a megjelenítő: 
Adja ki a(z) „gedit --help” parancsot az elérhető parancssori kapcsolók teljes listájáért.