"geometry does not match label"

[Christian Weisgerber]

On booting a new kernel, I noticed a piece of kernel spew I don't
remember seeing before:

GEOM: ad6s1: geometry does not match label.

bsdlabel offers suitably scary warnings:

$ bsdlabel ad6s1
# /dev/ad6s1:
8 partitions:
#        size   offset    fstype   [fsize bsize bps/cpg]
  a:  2097152       63    4.2BSD     2048 16384 28528 
  b:  8396800  2097215      swap                    
  c: 293041602       63    unused        0     0         # "raw" part, don't edit
  d: 20971520 10494015    4.2BSD     2048 16384 28528 
  e:  2097152 31465535    4.2BSD     2048 16384 28528 
  f: 62914560 33562687    4.2BSD     2048 16384 28528 
  g: 62914560 96477247    4.2BSD     2048 16384 28528 
  h: 133649858 159391807    4.2BSD     2048 16384 28528 
partition c: partition extends past end of unit
bsdlabel: partition c doesn't start at 0!
bsdlabel: An incorrect partition c may cause problems for standard system utilities
partition h: partition extends past end of unit

I don't know where this is coming from--the system was installed
about a year ago with standard sysinstall--and I don't see what's
supposed to be wrong.

$ gpart show
=>       63  293046705  ad6  MBR  (140G)
         63  293041602    1  freebsd  [active]  (140G)
  293041665       5103       - free -  (2.5M)

=>        0  293041602  ad6s1  BSD  (140G)
          0    2097152      1  freebsd-ufs  (1.0G)
    2097152    8396800      2  freebsd-swap  (4.0G)
   10493952   20971520      4  freebsd-ufs  (10G)
   31465472    2097152      5  freebsd-ufs  (1.0G)
   33562624   62914560      6  freebsd-ufs  (30G)
   96477184   62914560      7  freebsd-ufs  (30G)
  159391744  133649858      8  freebsd-ufs  (64G)

Ideas?

-- 
Christian "naddy" Weisgerber                          naddy at mips.inka.de