Comment 68 for bug 1573959

That would be how fixing bugs for ubuntu is supposed to work:

 - you find a way to reproduce the bug
 - Even if you only know that the bug was fixed within the last 256 commits to the kernel's git repository git bisect will let you test only 8 versions of the source code - and after you testing them it is already able to tell which commit was the right one
 - git format-patch generates a patch
 - you forward the patch to the packager
 - and all is set.

The only thing missing until now is the 1st step: Finding a way to reliably reproduce the bug.