kern/150761: Kernel panic at devclass_get_name when doing heavy pkg_add

[Kris Moore]

>Number:         150761
>Category:       kern
>Synopsis:       Kernel panic at devclass_get_name when doing heavy pkg_add
>Confidential:   no
>Severity:       critical
>Priority:       high
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Mon Sep 20 17:20:00 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Kris Moore
>Release:        9.0-Current
>Organization:
iXsystems
>Environment:
FreeBSD pcbsd 9.0-CURRENT FreeBSD 9.0-CURRENT #6: Thu Sept 16 08:56:22 PDT 2010
>Description:
Getting a consistent kernel panic while doing an installation and a bunch of pkg_add work is being done. Funny thing is, that when using ZFS file-system for installation, it finishes properly, but when I switch to UFS + Softupdates this panic occurs like clockwork. That may not be related, but it is a weird quirk none the less.

Screenshot of panic:
http://www.pcbsd.org/~kris/kerndump/panic1.png

Core file:
http://www.pcbsd.org/~kris/kerndump/vmcore.0.gz

Let me know if you need additional info.

(As an aside, seeing similar panics on 8.0 / 8.1, when our installer is doing pkg_delete / pkg_add stuff in the disk chroot environment)
>How-To-Repeat:
Just starting an install of PC-BSD / FreeBSD 9.0 snapshots, works fine until it gets into heavy duty pkg_add stuff, then this panic occurs.
>Fix:
Using ZFS works, but it may be an unrelated quirk. 

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