$ ps -o pid,stat,wchan,command -p 31041
   PID STAT   WCHAN    COMMAND
 31041 D1     ums lock /bin/sh /tmp/ocloop.sh
$ ps axww | grep ocloop
 31041 ??  D1       0:01.85 /bin/sh /tmp/ocloop.sh
# D1 = stuck in kernel, "ums lock" = &sc->sc_lock (lockinit name, ums.c:593)
# kill -9 delivered 1s earlier; process still present (unkillable)