Solved by installing the kernel from http://kernel.ubuntu.com/~kernel-ppa/mainline/daily/2015-02-10-vivid/ leading to "3.19.0-999-generic #201502092105"
According to https://bugzilla.kernel.org/show_bug.cgi?id=92981 the kernel on http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.19-vivid/ was built incorrectly
Solved by installing the kernel from http:// kernel. ubuntu. com/~kernel- ppa/mainline/ daily/2015- 02-10-vivid/ leading to "3.19.0-999-generic #201502092105"
According to https:/ /bugzilla. kernel. org/show_ bug.cgi? id=92981 the kernel on http:// kernel. ubuntu. com/~kernel- ppa/mainline/ v3.19-vivid/ was built incorrectly