Processes stuck in [vmo_de]

Was doing a local build on a VMWare 8.x image today, and ran into this:

rm -f .newdep
make -V CFILES -V SYSTEM_CFILES -V GEN_CFILES |  MKDEP_CPP="cc -E" CC="cc" 
xargs mkdep -a -f .newdep -O -pipe  -std=c99 -g -Wall -Wredundant-decls 
-Wnested-externs -Wstrict-prototypes  -Wmissing-prototypes -Wpointer-arith 
-Winline -Wcast-qual  -Wundef -Wno-pointer-sign -fformat-extensions -nostdinc 
-I. -I../../.. -I../../../contrib/altq -I../../../contrib/ipfilter 
-I../../../contrib/pf -I../../../dev/ath -I../../../dev/ath/ath_hal 
-I../../../contrib/ngatm -I../../../dev/twa -I../../../gnu/fs/xfs/FreeBSD 
-I../../../gnu/fs/xfs/FreeBSD/support -I../../../gnu/fs/xfs 
-I../../../contrib/opensolaris/compat -I../../../dev/cxgb -D_KERNEL 
-DHAVE_KERNEL_OPTION_HEADERS -include opt_global.h -fno-common 
-finline-limit=8000 --param inline-unit-growth=100 --param 
large-function-growth=1000  -mno-align-long-strings 
-mpreferred-stack-boundary=2  -mno-mmx -mno-3dnow -mno-sse -mno-sse2 -mno-sse3 
-ffreestanding -fstack-protector


load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
^Z
Suspended
robert_at_cinnamon-freebsd:~/freebsd/svncommit/base/head/sys/i386/compile/GENERIC> 
bg
[1]    make depend &
robert_at_cinnamon-freebsd:~/freebsd/svncommit/base/head/sys/i386/compile/GENERIC> 
fg
make depend


load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
load: 0.20  cmd: xargs 5100 [piperd] 0.02r 0.00u 0.00s 0% 1592k
^C

load: 0.20  cmd: sh 5099 [vmo_de] 0.02r 0.00u 0.00s 0% 0k
load: 0.20  cmd: sh 5099 [vmo_de] 0.02r 0.00u 0.00s 0% 0k
^C^C^C


load: 0.20  cmd: sh 5099 [vmo_de] 0.02r 0.00u 0.00s 0% 0k
load: 0.20  cmd: sh 5099 [vmo_de] 0.02r 0.00u 0.00s 0% 0k
^C^C^C


(another pty)
robert_at_cinnamon-freebsd:~/freebsd/svncommit/base/head/sys/sys> ps axl
   UID   PID  PPID CPU PRI NI   VSZ   RSS MWCHAN STAT  TT       TIME COMMAND
...
  1001  5038  5037   0  76  0  5592  3012 pause  Ss     4    0:00.00 -tcsh 
(tcsh
  1001  5054  5038   0  76  0  8032  6764 wait   S+     4    0:00.00 make 
depend
  1001  5098  5054   0  76  0  3572  1796 wait   S+     4    0:00.00 [sh]
  1001  5099  5098   0  76  0     0     8 vmo_de D+     4    0:00.00 [sh]

And unfortunately:

robert_at_cinnamon-freebsd:~/freebsd/svncommit/base/head/sys/i386/compile/GENERIC> 
su
Password:

load: 0.20  cmd: csh 5120 [vmo_de] 0.00r 0.00u 0.00s 0% 0k
load: 0.20  cmd: csh 5120 [vmo_de] 0.00r 0.00u 0.00s 0% 0k
load: 0.20  cmd: csh 5120 [vmo_de] 0.00r 0.00u 0.00s 0% 0k

FreeBSD cinnamon-freebsd 8.0-CURRENT FreeBSD 8.0-CURRENT #5 r193116M: Sun May 
31 10:14:00 BST 2009 
robert_at_cinnamon-freebsd:/usr/home/robert/freebsd/svncommit/base/projects/pnet/sys/i386/compile/GENERIC 
i386

This appears to be head from a few days ago, but I don't have a specific 
source code date.  Unfortunately, no BREAK_TO_DEBUGGER, and I can't su to 
enter via debug.kdb.enter.

Robert N M Watson
Computer Laboratory
University of Cambridge