[Pkg-sysvinit-devel] Bug#670106: initscripts: please ignore noauto sysfs entries in fstab

[Carsten Hey]

Package: initscripts


Bug summary:

Please ignore noauto sysfs entries in fstab.  Not mounting sysfs to /sys
if such a line is present in fstab leads to udev not starting.

If this bug is not fixed, this problems will show up after upgrading to
Wheezy on some systems.


Bug details:

Gregor Thill noted:
| When bootstrapping Wheezy, the (grml-debootstrap) script creates an
| fstab including a line for sysfs with the mount option noauto. During
| boot of the resulting Debian system, sysfs won't be mounted and as
| udev depends on it, udev does not run. Removing the line or the noauto
| option fixes this behaviour.

Only changing grml-debootstrap to not to create this line, as already
reported in Debian bug #670074, won't solve this problem for all those
pre-Wheezy systems created using "buggy" grml-debootstrap versions.  The
problem will be noticed after an upgrade to Wheezy since
initscripts/Squeeze (or less likely, anything else installed by default
on Squeeze) mounts sysfs despite a noauto sysfs fstab entry.

The line added to /etc/fstab is:
  /sys   /sys   sysfs   noauto,rw,nosuid,nodev,noexec   0   0

I don't think such an entry will only occur on systems installed using
grml-debootstrap, and I think initscripts should be adapted to ignore
a noauto fstab entry for /sys, even if you might consider such and line
to be buggy.

The initscript responsible for mounting sysfs to /sys seems to be
/etc/init.d/mountkernfs.sh, which uses a function in
/lib/init/mount-functions.sh to do so.


Regards
Carsten