Thanks for your report.
The error message from dmesg.log
8815.994694] ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
[ 8815.994705] ata1.00: BMDMA stat 0x24
[ 8815.994714] ata1.00: failed command: WRITE DMA EXT
[ 8815.994732] ata1.00: cmd 35/00:10:08:8c:bd/00:01:03:00:00/e0 tag 0 dma
** Attachment added: "Df.txt"
http://launchpadlibrarian.net/50999733/Df.txt
** Attachment added: "Dmesg.txt"
http://launchpadlibrarian.net/50999734/Dmesg.txt
** Attachment added: "DpkgTerminalLog.txt"
http://launchpadlibrarian.net/50999735/DpkgTerminalLog.txt
--
package xul-ext-gears