Bug#742392: hurd: Hang during apt-get upgrade from last image release

[Petter Reinholdtsen <pere@hungry.com>]

I got some help from gg0 on IRC to debug this issue.  He proposed to
upgrade everything except hurd first, and this worked:

  apt-get update
  apt-mark hold hurd
  apt-get dist-upgrade
  apt-mark unhold hurd

This reduced the amount of packages to upgrade to the minimum.
Upgrading using apt-get dist-upgrade now also hung, but it was a lot
quicker to test as I had snapshotted the freshly upgraded system.

We tried adding a serial console (adding
GRUB_CMDLINE_GNUMACH="console=com0" in /etc/default/grub and running
update-grub) and see if anything showed up there.  No messages showed
up in the serial console when the system got stuck.  I did however
notice that the hang caused the machine to no longer respond to ping,
and my ssh connections would stop working too.

Last, I tried to upgrade over ssh (instead of the console I had tried
initially, and then I got a bit more text before the machine went
dead:

  root@debian:~# apt-get dist-upgrade
  Reading package lists... Done
  Building dependency tree       
  Reading state information... Done
  Calculating upgrade... Done
  The following packages will be REMOVED:
    libdb5.1
  The following NEW packages will be installed:
    login
  The following packages will be upgraded:
    db5.1-util hurd hurd-dev hurd-libs0.3
  4 upgraded, 1 newly installed, 1 to remove and 0 not upgraded.
  Need to get 1351 kB/6117 kB of archives.
  After this operation, 2894 kB of additional disk space will be used.
  Do you want to continue? [Y/n] 
  Get:1 http://cdn.debian.net/debian/ sid/main login hurd-i386 1:4.1.5.1-1.1 [695 kB]
  Get:2 http://cdn.debian.net/debian/ sid/main db5.1-util hurd-i386 5.1.29-8 [656 kB]
  Fetched 1351 kB in 7s (177 kB/s)                                                                      
  Reading changelogs... Done
  (Reading database ... 38608 files and directories currently installed.)
  Preparing to unpack .../hurd-dev_1%3a0.5.git20140320-1_hurd-i386.deb ...
  Unpacking hurd-dev (1:0.5.git20140320-1) over (1:0.5.git20140203-1) ...


  Preparing to unpack .../hurd-libs0.3_1%3a0.5.git20140320-1_hurd-i386.deb ...
  Unpacking hurd-libs0.3:hurd-i386 (1:0.5.git20140320-1) over (1:0.5.git20140203-1) ...
  Setting up hurd-libs0.3:hurd-i386 (1:0.5.git20140320-1) ...
  Processing triggers for libc-bin (2.18-3) ...
  (Reading database ... 38608 files and directories currently installed.)
  Preparing to unpack .../hurd_1%3a0.5.git20140320-1_hurd-i386.deb ...
  Unpacking hurd (1:0.5.git20140320-1) over (1:0.5.git20140203-1) ...
  Setting up hurd (1:0.5.git20140320-1) ...
  Installing new version of config file /etc/hurd/rc ...
  Installing new version of config file /etc/init.d/hurd-console ...

Not sure how to continue, as gg0 is not able to reproduce the problem,
but at least here it happen every time.

-- 
Happy hacking
Petter Reinholdtsen