[coreboot] Convert Assembly JMP to C

Joseph Smith joe at settoplinux.org
Fri Sep 12 00:05:46 CEST 2008

On Thu, 11 Sep 2008 16:03:04 -0600, Jordan Crouse <jordan.crouse at amd.com>
> On 11/09/08 17:49 -0400, Joseph Smith wrote:
>> OK,
>> My JMP question is about copying a drives mbr to memory 0x7c00 and or
>> 0x0600 at 512 byte
>> blocks. Which is doable. I haven't decided wetheir to try Ron's
> suggestion
>> and try to execute the mbr (hence the JMP question) OR we could even
> write
>> code to translate the mbr and JMP/execute directly to the active
> bootable
>> partition OR even better we could write code translate the mbr, goto the
>> active bootable partition and translate it, and JMP/execute right to the
>> boot manager, thus bypassing a whole bunch of real mode interrupts. What
> do
>> you think?
> You won't be successful.  Any executable code in any MBR is going to use
> real mode software interrupts.  You can't get around that, you shouldn't
> try.  We have very intellegent payloads that can boot any operating
> imaginable.  Use that.
Ah, Jordan you speak to soon. I have learn a way to setup a simple real
mode interrupt handler, capable of sending generic/dummy responses back to
the software....

Joseph Smith

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