kern/41811: mounting unconfigured vnd devices causes a hang

[lloyd%must-have-coffee.gen.nz@localhost]

>Number:         41811
>Category:       kern
>Synopsis:       mounting unconfigured vnd devices causes a hang
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    kern-bug-people
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Tue Aug 04 05:40:00 +0000 2009
>Originator:     Lloyd Parkes
>Release:        5.99.12
>Organization:
Must Have Coffee
>Environment:
NetBSD evbarm 5.99.12 NetBSD 5.99.12 (TS7200) #3: Tue Aug  4 15:54:46 NZST 2009 
 
lloyd%rhox.must-have-coffee.gen.nz@localhost:/vol/scratch/build-gsoc/obj.evbarm/sys/arch/evbarm/compile/TS7200
 evbarm

>Description:
Trying to mount a filesystem from a vnd device before you have remembered to 
configure the device causes the mount command to hang. 

# /sbin/mount -t ffs /dev/vnd1a /mnt
^C
# ps ax
PID TTY STAT    TIME COMMAND
  0 ?   DKl  0:23.48 [system]
  1 ?   Is   0:00.24 init 
204 ?   D    0:00.04 mount_ffs /dev/vnd1a /mnt 
230 ?   Is   0:00.83 login 
234 ?   S    0:00.16 -csh 
235 ?   O+   0:00.07 ps -ax 

>How-To-Repeat:
/sbin/mount -t ffs /dev/vnd1a /mnt

>Fix: