[Pkg-utopia-maintainers] Bug#545032: Bug#545032: Bug#545032: devicekit-disks - Handles add actions of dm devices

[Bastian Blank]

On Sun, Oct 11, 2009 at 09:04:09PM +0200, Andreas Barth wrote:
> As what I read from the bug report, Bastian prefers to have all udev
> rules in dmsetup.

Not in dmsetup, but in the package that controls that sort of device. So
dmsetup for the core rules, lvm2 for the lvm specific rules, cryptsetup
for their rules (if necessary, I don't know). Because they control there
own devices, they may also break it.

> Bastian, same questions to you: Is there any reason why we can't at
> all have a working set of udev rules in devicekit-disks? (I'm not
> necessarily speaking about the current rules, but why it is impossible
> to have any udev rules in the package at all.)

As long as the rules only change the behaviour of the tools in this
package, but not just copy other rules and also follow the other rules
about introspection, I don't see a general problem.

However, the current rules file does the following.
- Probe for partitions, aka open, on all block devices with a (small)
  blacklist. This can be only allowed with a whitelist, as several
  device types may not be queried from add events or not at all, like
  several dm subtypes.
- Try to get informations about dm devices from add events.
- Use blkid on dm devices even if this are hidden devices that must not
  show up via filesystem infos. Also done from add events, something
  that can never be allowed.
- Examine linux raid devices with mdadm. This is the sole responsibility
  of the mdadm package.
- Examine SMART state, only set informations.
- Tag devices without known prefix and with an undocumented list of
  devices.

The first point needs to be changed to a whitelist. The second only
provides information used by them but it is undetermined if it will
work and newer kernels change the way to actually get the information in
this state. The third one needs to go. The forth is not my problem but I don't
like it. The fifth is okay. The informations set in the sixth should get
a known prefix.

Bastian

-- 
Power is danger.
		-- The Centurion, "Balance of Terror", stardate 1709.2