This patch fixes a bug in aufs that can cause docker processes to enter
a defunct state but still consume 100% cpu. The processes are unkillable
as is the entire docker container, with the only recourse being to reboot
the machine. The problem was reported to Debian in the following report:
https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=812207
Message #47 in that exchange contains two patches which resolve the problem,
and this commit is the simple combination of those two.
96688fd4dd