Comment # 12 on bug 975824 from Takashi Iwai

Oh, you didn't have to check each version via "git reset".  git reset was
needed only for the first good and the first bad commits.  The rest points to
be tested are suggested by "git bisect" itself.

So, you already figured out that it's between 4.1.17 and 4.1.18.  Now try to
figure out which exact commit causes a regression.

Run like:
  % git bisect start
    (this might complain that it's being bisected, but then it's OK)
  % git bisect good v4.1.17
  % git bisect bad v4.1.18
After narrowing by these two points, git bisect will suggest a new point for
you to test.  Just build the kernel at this point, simply run "make" and
install as usual.  Boot with this test kernel, and run "git commit good" if
it's working, and "git commit bad" if it doesn't work.  Then git will suggest
another point to test.

This process is repeated until git bisect reaches to the culprit commit.