[syslinux] Looking for debugging ideas and help with testing

Ferenc Wagner wferi at niif.hu
Mon Dec 13 17:09:34 PST 2010


"H. Peter Anvin" <hpa at zytor.com> writes:

> On 12/13/2010 02:34 PM, Ferenc Wagner wrote:
>> 
>> The theory is that the boot.img.gz-s fail to boot correctly if written
>> to a full disk device (/dev/sda), but work fine if written to a
>> partition (/dev/sda1) and invoked by some MBR (see #604245).  No theory
>> about the ISO, but the reported symptoms are rather similar.  Anybody
>> inclined to help, please test whether the above images (or other similar
>> ones) fail to boot the Debian Installer on their systems.  Thanks.
>
> Most likely the problem is that the newer Syslinux misidentifies
> something in memory as a partition handover structure.
>
> Someone -- and I can't remember who right now -- built a debugging MBR
> for testing this case.

Do you mean Gene Cumm's mbrho.S?  I built that right now, under Qemu it
prints

DL: 80  DS: 0000  SI: 0000
 53 FF 00 F0 53 FF 00 F0 53 FF 00 F0 53 FF 00 F0
ES: 0000  DI: FFAC
 00 00 D4 CC

I can't make much sense of this, but anyway...  Should I get the
submitters run this?  Could this affect Isolinux as well?
-- 
Thanks,
Feri.




More information about the Syslinux mailing list