mountall counts remounts again, causing the boot procress to stop

For some reason, mountall failed at the last reboot of my home server. The box processes a few first boot steps and stops in an early boot phase. Weirdly, if the bootloader passed --verbose to the kernel, the boot process went well.
I compared the logs of a failed and a successful boot process and nailed it down to mountall, struggling with a bind mount of a read-only root fs. Apparently, mountall counted the remounts again as mounts, causing the total mount count to differ from the expected mount count. Therefore, the events local-filesystems and filesystems have not been emitted.

Watch for lines related to /mnt/root in mountall.log, this mount is counted four times instead of just once.

Workarounds:
1. Boot with init=/bin/sh, open a getty instance, exec init and run mountall there after the boot process has been stuck.
2. Set the problematic mount to noauto and mount it by yourself later.

One additional remark: This issue appeared the first time two days ago, without having changed anything at all at my fstab. During the uptime of ~10 days, a few packages have been installed or updated, but nothing mission critical. I have no idea what triggered this issue.

$ lsb_release -rd
Description: Ubuntu 14.04.1 LTS
Release: 14.04

$ apt-cache policy mountall
mountall:
  Installiert: 2.53
  Installationskandidat: 2.53
  Versionstabelle:
 *** 2.53 0
        500 http://ports.ubuntu.com/ubuntu-ports/ trusty/main armhf Package
        100 /var/lib/dpkg/status