amd64 kernel modules: mapping sections to addresses

John Baldwin jhb at
Mon Jun 21 20:15:53 UTC 2010

On Monday 21 June 2010 11:57:17 am Andriy Gapon wrote:
> on 21/06/2010 18:43 John Baldwin said the following:
> > np@ has a patch to gdb to fix this for kgdb.  I haven't committed it as it 
> > patched gdb internals and wasn't in a kgdb-specific place, but I'm not 
sure of 
> > a better way to fix kgdb.
> Oh, yes, section mapping is done in common gdb code.
> Perhaps kld.c shouldn't call build_section_table, but directly call
> bfd_map_over_sections with a custom variant of add_to_section_table?
> Can you please share the patch?

It was deeper level than that, I'd have to dig it up.

> Still, what about a small tool, elf(3)-base porgram or objdump+objcopy shell
> script, that would set section addresses in amd64 .ko (relocatable object 
> similarly to how they are set in i386 .ko (full-blown DSO)?
> Or is this too much useless hassle?

No idea.  If this worked and just let gdb work automatically that would be a 
nice fix to just put into the build process.

John Baldwin

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