boot2 -- Round 2

Jeremy Chadwick freebsd at
Fri Jul 30 14:28:55 PDT 2004

So, in regards to the commited fix:

This seemed to fix the issue on one of my boxes (the one which was
flat-out panic'ing, not the one which was reporting 0:ad(0,`) as the
default slice to load /boot/loader from).  I'll refer to the one which
panic'd as "Box A" while the one which is doing the backtick as "Box B".

After pulling cvs down last night and rebuilding world+kernel+boot
blocks, running disklabel -B ad0s1, all on Box B, I found the machine
once again spitting out "Invalid partition", trying to load loader(8)
off of 0:ad(0,`) instead of 0:ad(0,a).  I double-checked boot2/Makefile
to see if -fno-unit-at-a-time was in place -- and it was.

I've tried using /boot/boot off of Box A and applying it to Box B using
disklabel -B -b /boot/box_b/boot ad0s1 to no avail.

It seems almost as if the boot2 code is broken in such a way that it
resembles an "off-by-one" error (ASCII 0x60 == `, ASCII 0x61 == a).
Why it's picking ` is beyond me...

Can someone shed some light as to how I can go about debugging this,
as well as mention how I can temporarily work around this?  Box B
happens to run mysqld, and is suffering from some issues mentioned on
freebsd-threads (re: machine randomly hard-locking), so it definitely
needs to be able to boot back up on it's own without my intervention.


| Jeremy Chadwick                                 jdc at |
| Parodius Networking               |
| UNIX Systems Administrator                   Mountain View, CA, USA |
| Making life hard for others since 1977.                             |

More information about the freebsd-current mailing list