Re: [RFC] ELF Relocatable x86 and x86_64 bzImages

Jan Kratochvil
2006-08-01T20:14:29Z

On Tue, 01 Aug 2006 21:26:28 +0200, Vivek Goyal wrote:
...
> Can't we use the x86_64 relocation approach for i386 as well? I mean keep
> the virtual address space fixed and updating the page tables. This would
> help in the sense that you don't have to change gdb if somebody decides to
> debug the relocated kernel.

This is exactly the approach of mkdump version <=1.0
http://mkdump.sourceforge.net/
As documented by Itsuro Oda:
http://mkdump.cvs.sourceforge.net/mkdump/doc/mini_kernel_tech_note.txt?revision=1.1

There is a problem all the drivers expect that allocated buffer address can be
passed directly as physical address to the hardware. mkdump-1.0 has a lot of
backward-mappings for these drivers but you can never catch all of them.

Regards,
Lace