Failed update

[Richard Mahlerwein]

--- On Sun, 8/9/09, Richard Mahlerwein <mahlerrd at yahoo.com> wrote:

> From: Richard Mahlerwein <mahlerrd at yahoo.com>
> Subject: Re: Failed update
> To: "FreeBSD-Questions" <freebsd-questions at freebsd.org>
> Date: Sunday, August 9, 2009, 11:34 AM
> --- On Sun, 8/9/09, Richard
> Mahlerwein <mahlerrd at yahoo.com>
> wrote:
> 
> > From: Richard Mahlerwein <mahlerrd at yahoo.com>
> > Subject: Failed update
> > To: "FreeBSD-Questions" <freebsd-questions at freebsd.org>
> > Date: Sunday, August 9, 2009, 10:23 AM
> > In upgrading 7.1-PRELEASE to -stable,
> > all seemed fine until I rebooted out of single user
> mode
> > after doing make installworld and mergemaster.
> > 
> > Now I get to devd and it dies.  I've copied down
> > what's on screen and typed it here.
> > 
> > ****
> > [snip]
> > starting devd.
> > 
> > Fatal trap 12: page fault while in kernel mode.
> > cpu id = 0; apic id = 00
> > fault virtual address = 0x3030313a
> > fault code = supervisor write, page not present
> > [snip]
> > current process = 355 (devd)
> > 
> > ****
> > 
> > What critical step did I miss?  Single user mode
> seems
> > OK, and I can mount the drives (though right now it'll
> tell
> > me to fsck, since I just hard crashed).  I have not
> > tried to cycle this thing much, for fear of trashing
> > something further, but I did at least try one
> reboot. 
> > Same issue.
> > 
> > (and yes, I'll be researching this myself, but I
> thought
> > I'd get this message out there sooner rather than
> later...)
> > 
> > Rich Mahlerwein
> 
> I'm redoing the whole process in single user mode.  My
> guess is I goofed something during mergemaster and devd.conf
> is messed up.  (Mergemaster is, undeniably, my least
> favorite utility).  
> 
> I can suffer the system being down for a while, as long as
> my wife has access to a handful of files.  
> 
> How would I go about mounting a USB stick, if such can be
> done in single-user mode?  
> 
> I have several sitting around that I could copy stuff to
> (I'm sure that's easier than pulling off the backup I made
> last night, since the backup is in dump format on tape, and
> since my only bsd box is currently not working...)

I'll answer my own question: 
mount -t msdosfs /dev/da0s1 /mnt
then copy away at will.  I suppose my biggest issue had been wondering if that works in single user mode.