panic due to 'ds_len > SBP_SEG_MAX'

[Garance A Drosihn]

I have freebsd 7.x running on a PowerPC Mac-Mini.  The hard disk in
a mac mini is rather slow, so I have freebsd installed on an external
firewire drive.  The way it's setup, all the filesystems (including
'/') are on that external firewire drive.  This has been working okay
for awhile.

This past Sunday I updated my 7.x source tree and compiled everything.
When I tried to boot up with the new kernel, I hit a panic:

   trying to mount root from ufs:/dev/da0s9
   panic: ds_len > SBP_SEG_MAX, fix busdma code
   KDB: enter: panic

At the time I was already running late for something else, so I
just rebooted into the old kernel and went back to running that.
The older kernel was compiled on May 30th.  The check I ran into
is in sys/dev/firewire/sbp.c , and has been there for years, so
it isn't a new check.

Has anyone else seen this?

-- 
Garance Alistair Drosehn            =   gad at gilead.netel.rpi.edu
Senior Systems Programmer           or  gad at freebsd.org
Rensselaer Polytechnic Institute    or  drosih at rpi.edu