pcmcia ioctl removal

[Willy Tarreau]

On Tue, May 01, 2007 at 05:16:13AM -0400, Robert P. J. Day wrote:
> On Tue, 1 May 2007, Christoph Hellwig wrote:
> 
> > >  pcmcia-delete-obsolete-pcmcia_ioctl-feature.patch
> >
> > ...
> >
> > > Dominik is busy.  Will probably re-review and send these direct to Linus.
> >
> > The patch above is the removal of cardmgr support.  While I'd love
> > to see this cruft gone it definitively needs maintainer judgement on
> > whether they time has come that no one relies on cardmgr anymore.
> 
> since i was the one who submitted the original patch to remove that
> stuff, let me make an observation.
> 
> when i submitted a patch to remove, for instance, the traffic shaper
> since it's clearly obsolete, i was told -- in no uncertain terms --
> that that couldn't be done since there had been no warning about its
> impending removal.
> 
> fair enough, i can accept that.
> 
> on the other hand, the features removal file contains the following:
> 
> ...
> What:   PCMCIA control ioctl (needed for pcmcia-cs [cardmgr, cardctl])
> When:   November 2005
> ...
> 
> in other words, the PCMCIA ioctl feature *has* been listed as obsolete
> for quite some time, and is already a *year and a half* overdue for
> removal.
> 
> in short, it's annoying to take the position that stuff can't be
> deleted without warning, then turn around and be reluctant to remove
> stuff for which *more than ample warning* has already been given.
> doing that just makes a joke of the features removal file, and makes
> you wonder what its purpose is in the first place.
> 
> a little consistency would be nice here, don't you think?

No, it just shows how useless this file is. What is needed is a big
warning during usage, not a file that nobody reads. Facts are :

  - 90% of people here do not even know that this file exists
  - 80% of the people who know about it do not consult it on a regular basis
  - 80% of those who consult it on a regular basis are not concerned
  - 75% of statistics are invented

=> only 20% of 20% of 10% of those who read LKML know that one feature
   they are concerned about will soon be removed = 0.4% of LKML readers.

If you put a warning in kernel messages (as I've seen for a long time
about tcpdump using obsolete AF_PACKET), close to 100% of the users
of the obsolete code who are likely to change their kernels will notice
it.

I'm sorry for your patch which may get delayed a lot. You would spend
fewer time stuffing warnings in areas affected by scheduled removal.

BTW, I'm not even against the end of cardmgr support, it's just that
I don't know what the alternative is, and I suspect that many users
do not either. A big warning would have brought them to google who
would have provided them with suggestions for alternatives.

Willy