Comment 57 for bug 1514233

Greetings!

I had to bisect the Mainline kernels after all.

The highest kernel version that is not showing the issue is: Ubuntu-4.1.0-3.3 (Mainstream 4.1.3).
The next kernel version is Ubuntu-4.2.0-7.7 (Mainstream 4.2.0) and that is showing the issue.
The tests in detail below.

How to proceed from here?

MAINLINE KERNELS

vivid linux
3.19.0-32.37 Ubuntu-3.19.0-32.37 3.19.8-ckt7 kernel used before upgrading to wily, does not have issue
3.19.0-33.38 Ubuntu-3.19.0-33.38 3.19.8-ckt7
3.19.0-37.42 Ubuntu-3.19.0-37.42 3.19.8-ckt9
3.19.0-39.44 Ubuntu-3.19.0-39.44 3.19.8-ckt9
3.19.0-41.46 Ubuntu-3.19.0-41.46 3.19.8-ckt10
3.19.0-42.48 Ubuntu-3.19.0-42.48 3.19.8-ckt10 (last Vivid kernel, not tested for issue)

Wily linux

3.19.0-20.20 Ubuntu-3.19.0-20.20 3.19.8
4.0.0-4.6 Ubuntu-4.0.0-4.6 4.0.7
4.0.0-4.7 Ubuntu-4.0.0-4.7 4.0.7 works fine, issue not found here
4.1.0-1.1 Ubuntu-4.1.0-1.1 4.1.0
4.1.0-2.2 Ubuntu-4.1.0-2.2 4.1.3
4.1.0-3.3 Ubuntu-4.1.0-3.3 4.1.3 works fine, issue not found here
4.2.0-7.7 Ubuntu-4.2.0-7.7 4.2.0 has issue
4.2.0-10.11 Ubuntu-4.2.0-10.11 4.2.0
4.2.0-10.12 Ubuntu-4.2.0-10.12 4.2.0 has issue
4.2.0-11.13 Ubuntu-4.2.0-11.13 4.2.1 has issue, at log in reporting an error with x
4.2.0-12.14 Ubuntu-4.2.0-12.14 4.2.1
4.2.0-14.16 Ubuntu-4.2.0-14.16 4.2.2 has issue
4.2.0-15.18 Ubuntu-4.2.0-15.18 4.2.3
4.2.0-16.19 Ubuntu-4.2.0-16.19 4.2.3 (Release Ref. https://launchpad.net/ubuntu/+source/linux-signed - not tested)
4.2.0-17.21 Ubuntu-4.2.0-17.21 4.2.3
4.2.0-18.22 Ubuntu-4.2.0-18.22 4.2.3 has issue
4.2.0-19.23 Ubuntu-4.2.0-19.23 4.2.6
4.2.0-21.25 Ubuntu-4.2.0-21.25 4.2.6
4.2.0-22.27 Ubuntu-4.2.0-22.27 4.2.6

Ref. http://people.canonical.com/~kernel/info/kernel-version-map.html

upstream kernel v4.3.0 has issue
upstream kernel v4.4.3 has issue