Comment 3 for bug 919321

Yep, looks like you had a GPU lockup.

[ 12024.839] [mi] EQ overflowing. The server is probably stuck in an infinite loop.
[ 12024.839]
Backtrace:
[ 12024.863] 0: /usr/bin/X (xorg_backtrace+0x26) [0x460566]
[ 12024.863] 1: /usr/bin/X (mieqEnqueue+0x201) [0x45a941]
[ 12024.863] 2: /usr/bin/X (xf86PostMotionEventM+0xa3) [0x4805d3]
[ 12024.863] 3: /usr/lib/xorg/modules/input/evdev_drv.so (0x7f7abca2b000+0x5f23) [0x7f7abca30f23]
[ 12024.863] 4: /usr/lib/xorg/modules/input/evdev_drv.so (0x7f7abca2b000+0x65fb) [0x7f7abca315fb]
[ 12024.863] 5: /usr/bin/X (0x400000+0x6da67) [0x46da67]
[ 12024.863] 6: /usr/bin/X (0x400000+0x121f2e) [0x521f2e]
[ 12024.863] 7: /lib/x86_64-linux-gnu/libpthread.so.0 (0x7f7ac421e000+0x10060) [0x7f7ac422e060]
[ 12024.863] 8: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f7abdf44000+0x896c0) [0x7f7abdfcd6c0]
[ 12024.863] 9: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f7abdf44000+0x8b2b5) [0x7f7abdfcf2b5]
[ 12024.863] 10: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f7abdf44000+0xf4ac2) [0x7f7abe038ac2]
[ 12024.863] 11: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f7abdf44000+0xf4e65) [0x7f7abe038e65]
[ 12024.863] 12: /usr/lib/x86_64-linux-gnu/xorg/extra-modules/nvidia_drv.so (0x7f7abdf44000+0x48237c) [0x7f7abe3c637c]
[ 12024.863] 13: /usr/bin/X (0x400000+0xe081c) [0x4e081c]
[ 12024.863] 14: /usr/bin/X (0x400000+0x2c87e) [0x42c87e]
[ 12024.863] 15: /usr/bin/X (0x400000+0x2fb89) [0x42fb89]
[ 12024.863] 16: /usr/bin/X (0x400000+0x232fe) [0x4232fe]
[ 12024.863] 17: /lib/x86_64-linux-gnu/libc.so.6 (__libc_start_main+0xed) [0x7f7ac314730d]
[ 12024.863] 18: /usr/bin/X (0x400000+0x235ed) [0x4235ed]
[ 12061.102]
Backtrace:
[ 12061.102] 0: /usr/bin/X (xorg_backtrace+0x26) [0x460566]
[ 12061.102] 1: /usr/bin/X (0x400000+0x64b6a) [0x464b6a]

Sounds similar to a couple other bugs recently reported. Unfortunately neither of the logs tell what GPU error you hit so impossible to say if it's a new bug or dupe.

Are you able to reproduce this bug? If so, for GPU lockup bugs what you need to provide is:

 * sudo dmesg > dmesg.txt
 * /sys/kernel/debug/dri/0/i915_error_state
 * /var/log/Xorg.0.log

These should be collected *while* the machine is locked up (or shortly thereafter if it recovers on its own). You might need to SSH into the machine to collect them.