kern.geom.debugflags=16 does NOT allow me to write to device

[Jeremy Chadwick]

On Thu, Apr 22, 2010 at 10:55:29PM +0200, Peter Schuller wrote:
> open() in O_RDWR fails on the device in question (which is "used" by
> glabel, indirectly by gmirror and zfs).
> 
> This is on an 8.0 userland and 8-STABLE kernel. This is a bit stupid I
> know (nevermind why), but given that a plain open() syscall is failing
> I highly doubt that it has anything to do with the userland being out
> of synch. I cannot imagine GEOM changing like that in between 8.0 and
> 8-STABLE before the 8.1 release (correct me if this is a poor
> assumption).
> 
> Observe:
> 
> % whoami
> root
> % sysctl -w kern.geom.debugflags=16
> kern.geom.debugflags: 16 -> 16
> % sysctl kern.geom.debugflags
> kern.geom.debugflags: 16
> % ktrace disklabel -B /dev/ad9s1
> disklabel: Class not found

You'd have seen this problem on 8.0-RELEASE as well.  I've been bitching
about it since trying out 8.0-RC1.  The "Class not found" errors have
existed for way too long, and are confusing people left and right.

Supposedly we're supposed to use gpart(8) now, but I haven't figured out
how to use it in the same way as bsdlabel.

-- 
| Jeremy Chadwick                                   jdc at parodius.com |
| Parodius Networking                       http://www.parodius.com/ |
| UNIX Systems Administrator                  Mountain View, CA, USA |
| Making life hard for others since 1977.              PGP: 4BD6C0CB |