misc/169908: Shutdown goes to panic, if swap device disappeared

[Alexander Yerenkow]

>Number:         169908
>Category:       misc
>Synopsis:       Shutdown goes to panic, if swap device disappeared
>Confidential:   no
>Severity:       non-critical
>Priority:       low
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Jul 16 12:20:09 UTC 2012
>Closed-Date:
>Last-Modified:
>Originator:     Alexander Yerenkow
>Release:        FreeBSD 9.0-RELEASE-p3
>Organization:
>Environment:
FreeBSD pc 9.0-RELEASE-p3 FreeBSD 9.0-RELEASE-p3 #0: Tue Jun 12 02:52:29 UTC 2012     root at amd64-builder.daemonology.net:/usr/obj/usr/src/sys/GENERIC  amd64

>Description:
Attempt to shutdown produce panic, if swap device disappeared.
>How-To-Repeat:
In my case:
I have eli ada1, after I attach it, there exist zfs pool.
I import it, and there I have plenty of space.
That's why I created there (in /zpool) 4g file, for using it as additional swap.

mdconfig -af /zpool/swapfile
md0

swapctl -a md0
And I have a lot of swap.
But if swap used a lot, when I'm trying to restart/shutdown I almost always got kernel panic.

If you'll need - I'll try to get foto of screen with panic.

>Fix:
None

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