i386/80969: Repeatable double fault panic after CARP was enabled

[Scott N]

>Number:         80969
>Category:       i386
>Synopsis:       Repeatable double fault panic after CARP was enabled
>Confidential:   no
>Severity:       serious
>Priority:       high
>Responsible:    freebsd-i386
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Fri May 13 10:50:02 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Scott N
>Release:        5.4 RC's and now 5.4 RELEASE
>Organization:
>Environment:
5.4-RELEASE i386
>Description:
Using pfsense as my firewall on an old Compaq Deskpro 2000 200mmx w/128mb ram. Two 3Com 905c-TX NIC's.

PFsense maintainer and I have narrowed the issue down to when they enabled CARP in the kernel. I run fine on any FreeBSD 5.3x and 5.4RCx BEFORE they turned on CARP. Once CARP was enabled I get a 100% reproducible panic when accesses the pfsense configuration webGUI.

After about 5 seconds into access the webgui through a webrowser, it stops responding and this information is on the screen of the pfsense/FreeBSD based box:

---
fatal double fault
eip = 0xc046f9b8
esp = 0xc7ab7000
ebp = oxc7ab7014
cpuid = 0; apic id = 00
panic: double fault
cpuid = 0
KDB: enter:panic
[ thread pid 22 tid 100016 ]
stopped at   kdb_enter+0x2b:nop
>How-To-Repeat:
pfsense on my Deskpro, access WebGUI. Started happening after CARP was enabled in the kernel of pfsense builds.

 
>Fix:
      
>Release-Note:
>Audit-Trail:
>Unformatted:
 >db
 
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 I am not verse enough to get you more information on my own as I am not a programmer. But I am more than willing to help with any info requested, with help, as this is very easy to reproduce for me.
 
 thanks