cvs commit: src/sys/boot/i386/cdboot cdboot.s

Maxim Sobolev sobomax at
Tue Apr 11 21:03:53 UTC 2006

John Baldwin wrote:
> On Tuesday 11 April 2006 10:34, Maxim Sobolev wrote:
>> boo1 does the same - timeout loop. My small research seemingly suggests 
>> that doing A20 via the BIOS is not very reliable and may not work on all 
>> machines.
> Can you test a patch for pxeboot?  It looks to be the one other place that
> goes near the A20 line.

Done. Returning to the subject, loader's version of A20-enabling routine 
suffers from the very same problem (libi386/gatea20.c), but luckily we 
don't use this routing in the loader at all. I suspect that it relies on 
A20 being enabled by previous boot stages.


More information about the cvs-src mailing list