BTX loader hangs after version info

[Mark Kirkwood]

James Seward wrote:
> Hello,
>
> Two days ago I csup'd my desktop at home, which was running RELENG_7
> from about 7.0-RELEASE time, to bring it up-to-date (still on
> RELENG_7). I followed my usual buildkernel/world procedure (the usual
> one) which has worked fine all the way since 5.x. After installing
> kernel and restarting in single user, it was working fine. However,
> following installworld it will not boot.
>
> It stops immediately after "BTX loader 1.00 BTX version 1.02", but
> with the cursor on the line *above* the first "B". Nothing futher
> happens, but the system responds to Ctrl-Alt-Del.
>
> I have managed to start it using the install CD and csup'd back to a
> version just before the commit to BTX that moved it to 1.02 (March
> 18th, I think). However, that version too hangs after "BTX loader 1.00
> BTX version 1.01".
>
> My desktop is currently building RELENG_7_0 to see if that will work,
> but I won't know that until later as I'm at work and it is at home :)
>
> The install CD (BTX 1.00/1.01) boots fine. Nothing else changed on my
> system between the last successful boot and the unsuccessful one.
>
> Any suggestions/advice for what I can try next, or what I can do to
> help the troubleshooting process?
>
> My desktop is an Athlon64 but I am using i386, on an Asus A8V-E Deluxe board.
>   
FWIW - I am seeing this too, on a Supermicro P3TDDE. 7-STABLE src from 
28-Feb is fine, but Mar, Apr, May code all hangs after printing "loading 
/boot/defaults/loader.conf" - presumably reading my /boot/loader.conf?

Interestingly I can usually get it to boot by escaping to the loader 
prompt and then just pressing return.

Oddly some other machines (Supermicro P3TDER and Asus PRO31J Laptop) 
behave normally with src from Mar->May.

In all cases the canonical procedure from UPDATING was used (buildworld, 
kernel, reboot single, mergemaster -p, installworld, delete-old, 
mergemaster, reboot).

I happy to help collect some debug info (how do you switch this on for 
the loader?), tho the machine exhibiting the problem is my workstation 
(of course)!

regards

Mark