Bug#248071: Hot plugged devices shouldn't be marked "auto"

[Thomas Hood <jdthood@aglu.demon.nl>]

On Mon, 2004-06-28 at 22:59, Per Olofsson wrote:
> I agree. But how do we provide a smooth upgrade here? Default to the
> new behaviour on new installations but ask using debconf during
> upgrades from earlier versions with the old behaviour?


Yes, that would be a good way.  And the debconf question is very
optional.  See my reply to Osamu Aoki in this bug report thread.



> > 2. pcmcia-cs does not ifup/ifdown interfaces on 16 bit PCMCIA cards
> >    by default (which requires a change to pcmcia-cs) and hw-detect
> >    lists such interfaces in /etc/network/devhotplug (as now).
> 
> This solution would be preferable, but is it feasible to make this
> change for sarge?


I can't think of any reason why we shouldn't make the change.  Of
course problems may turn up in testing; in that case we can revert
to #1.   I think we should attempt to move to #2 because the
"cleaner" the system we install in sarge the fewer difficulties
there will be upgrading systems to sarge+1.


> > Currently, pcmcia-cs ifups/ifdowns interfaces on 16 bit PCMCIA cards
> > and hw-detect lists such cards in /etc/network/devhotplug, which
> > is not one of the reasonable options: we shouldn't have hotplug and
> > cardmgr battling for control of those interfaces.
> 
> I agree that this is ugly, but is it a problem in practice?


Usually it will be harmless if "ifup" is run twice or "ifdown" is run
twice.  A case to worry more about is when "remove" and "add" are
generated close together.  (This sometimes happens.)  Then instead of

   ifdown, ifdown, ifup, ifup

you could get

   ifdown, ifup, ifdown, ifup

which would be bad, especially if things start using the network
after the first ifup.


Another problem: Detecting cardbusness
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
/var/run/stab tells us that a certain network interface is on a 16 bit
PCMCIA card.  Thus for a network interface on a 16 bit PCMCIA card we
can easily find out that it should (#1) be marked neither "auto"
nor "hotplug" or (#2) be marked "hotplug" in /etc/network/interfaces.

But how do we tell that a network interface is on a 32 bit PCMCIA
card?  Whether we choose #1 or #2, 32 bit PCMCIA cards have to be
handled by hotplug and so should be marked "hotplug" in /e/n/i.

It may be possible to do it using the information in /var/run/stab
and/or in the various /proc files.  I don't have a cardbus card so I
can't contribute much to figuring this out.
--
Thomas Hood