Adaptec AHA-1542CF boot problem in 5.3

[Scott Long]

george+freebsd at m5p.com wrote:
> Starting in at least Beta-6 and Beta-7 of FreeBSD 5.3, and in 5.3-RELEASE,
> FreeBSD dies after the 15-second SCSI settling timeout with an Adaptec
> AHA-1542CF.  This board worked in 5.2.1, 5.2, and up through 4.7.  Has
> anyone seen this board work with 5.3?              -- George Mitchell
> 

There is a known problem with ISA DMA in 5.3.  As a work-around, boot 
the CD and hit '6' to break to the loader command prompt.  Then type:

set vm.old_contigmalloc=1
boot

I believe that I have this fixed correctly in 5.3-STABLE/RELENG_5.  If 
the work-around works for you then try updating your sources and see
if it works without the above work-around.

Scott