kern/176471: xn driver crash on detach

[pete at helenius.fi]

>Number:         176471
>Category:       kern
>Synopsis:       xn driver crash on detach
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Feb 27 08:40:00 UTC 2013
>Closed-Date:
>Last-Modified:
>Originator:     Charlie Root
>Release:        FreeBSD 10.0-CURRENT amd64
>Organization:
>Environment:
System: FreeBSD f10master.secroom.net 10.0-CURRENT FreeBSD 10.0-CURRENT #3: Tue Feb 26 00:23:53 EET 2013 root at zfsmaster.secroom.net:/usr/obj/usr/src/sys/XENSR amd64


>Description:
	Using XenServer, detaching or changing configuration of xn network interface will lead to kernel panic in 9-STABLE and 10-CURRENT
>How-To-Repeat:
	Detach the interface when the VM is running
>Fix:
	Workaround is to shutdown the VM


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