In /sys/kernel/debug/ there isn't a dri folder. Previous attached file Xorg.log is a part of Xorg.0.log, the part in the moment of the freeze.
** Attachment added: "dmesg.txt" https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/919321/+attachment/2685436/+files/dmesg.txt -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/919321 Title: System freezes while watching a streaming video [xubuntu] To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/919321/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp