I have reported this to the freedesktop.org, and it seems that Chris Wilson, one of the moderator of the open-source Intel graphic driver, is been watching my bug report.
Here : https://bugs.freedesktop.org/show_bug.cgi?id=80229 ** Bug watch added: freedesktop.org Bugzilla #80229 https://bugs.freedesktop.org/show_bug.cgi?id=80229 -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1282867 Title: Frequent hang and render glitches in Xorg, caused by SNA To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1282867/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs