I tried again with "classic" LXC (not lxd), and there the FDs look differently: In xenial they point to /dev/pts/4, in yakkety they point to /dev/pts/1. But installing postgresql in both xenial and yakkety works fine.
I also tried with lxc-start-ephemeral, but in that case the low FDs are again pointing to /dev/null and things work fine (but I suppose you don't use emphemeral containers).
So, I'm happy to backport the patch, but I'm unable to create an SRU test case or verify the fix myself.
I tried again with "classic" LXC (not lxd), and there the FDs look differently: In xenial they point to /dev/pts/4, in yakkety they point to /dev/pts/1. But installing postgresql in both xenial and yakkety works fine.
I also tried with lxc-start- ephemeral, but in that case the low FDs are again pointing to /dev/null and things work fine (but I suppose you don't use emphemeral containers).
So, I'm happy to backport the patch, but I'm unable to create an SRU test case or verify the fix myself.