amd64/181704: ggatec crash the system when I write something into a device created by it under "ro" mode

[Kevin]

>Number:         181704
>Category:       amd64
>Synopsis:       ggatec crash the system when I write something into a device created by it under "ro" mode
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-amd64
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sat Aug 31 12:40:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Kevin
>Release:        9.1-RELEASE-p6
>Organization:
Home
>Environment:
FreeBSD Sky23eCao 9.1-RELEASE-p6 FreeBSD 9.1-RELEASE-p6 #0: Wed Aug 21 20:40:52 UTC 2013     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64
>Description:
When I tested the command seen on the book, system crashed and reboot automatically. After several minutes, the screen show "mountroot>".
Then I power off the machine, and start it again, SU+J recovering it.
>How-To-Repeat:
Tested in VirtualBox
VM A: 
IP:192.168.1.8

file:/etc/gg.exports:
192.168.1.10     RW     /dev/ada1

command:newfs -U /dev/ada1
command:ggated

VM B: 
IP:192.168.1.10
command:ggatec create -o ro 192.168.1.8 /dev/ada1
output:ggate0
command:mount /dev/ggate0 /mnt
command:touch /mnt/abcde
command:umount /mnt

CRASH!(VM B)
>Fix:


>Release-Note:
>Audit-Trail:
>Unformatted: