Bug#880504: Fixed upstream

[Andrew Chadwick <a.t.chadwick@gmail.com>]

Patching with Ronnie Sahlberg's f74bc7c[1] on top of the otherwise
affected Debian linux-image-4.14.0-rc7-amd64 using the handbook
test-patches instructions[2] fixes this bug for me. This was merged
upstream in 89db69d yesterday, and should be included in the next -rc
or 4.14.0 proper.

[1] https://github.com/torvalds/linux/commit/f74bc7c6679200a4a83156bb89cbf6c229fe8ec0.patch
[2] https://kernel-handbook.alioth.debian.org/ch-common-tasks.html#s4.2.2

-- 
Andrew Chadwick