On Sat, May 10, 2003 at 08:26:46PM -0700, Rick Smith wrote:
> I would be willing to upgrade memory to 4GB and/or modify the kernel to
> gain direct I/O functionality to/from PCI addresses 0xF0000000 through
> 0xF7FFFFFF. Could you recommend any resources (books, web sites, etc.) that
> would help guide me and understand what needs to be done? Thanks.
The easiest way is probably to upgrade memory.
Even in that case there may be still problems if someone checks PageReserved
somewhere in the VM for this, but if that happens it should be quite easy
I'm not sure there are books that are that intimate with the kernel.
Basically you would have to change the early boot path in
arch/i386/kernel/setup.c, arch/i386/mm/init.c to extend the mem_map.
Normally it gets the top of memory from the E820 map, you have to
overwrite this. mem= is not enough, because in this case it will
try to use non existing memory.