Instant reboot on new interface coming up

I've been having issues lately when trying to bring up a new interface. 
  It's a hard problem to actually see, because it makes my machine 
instantly reboot.

Here's what I see:
Normally, I use ath0 for wireless, and occasionally I use em0. 
Recently, when I was at a location with no wireless and no dhcp support, 
I powered up my laptop, plugged in to em0, and did an ifconfig em0 xxx. 
     After a few seconds, the system spontaneously reboots.  I figured 
out that killing dhclient on that interface before attempting to 
manually configure it helped.

Now, I also tried to connect using ppp to a GPRS network (via bluetooth 
through my cell phone).  This used to work just fine, probably a few 
months ago.   This time, I killed all dhclients, connected the bluetooth 
pieces, and then ran rfcomm_pppd, which creates a tun0 interface.  When 
the interface was created, and brought up without dhclient, everything 
worked ok.   When I accidentally left dhclient running, and tun0 was 
created, when the device got it's IP address, machine rebooted.

I have various machine logs/dmesg/etc here:
http://www.googlebit.com/freebsd/
(labeled by date - look for the most current versions)

I'm running 7.0-CURRENT as of a few days ago.

I have all the debugging, WITNESS, and other flags set.

Any ideas?


Eric


-- 
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Eric Anderson        Sr. Systems Administrator        Centaur Technology
Anything that works is better than anything that doesn't.
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