Re: Fast LKM symbol resolution with SysV ELH hash table

[Rusty Russell <rusty@rustcorp.com.au>]

On Tue, 20 Oct 2009 01:32:51 am Carmelo Amoroso wrote:
> 2009/10/19 Greg KH <greg@kroah.com>:
> > On Mon, Oct 19, 2009 at 01:45:20PM +0200, Carmelo Amoroso wrote:
> >> Just a few other notes. The current implementation I did based on SysV
> >> has a drawback that is not backward compatible, so you cannot use old
> >> modules with a kernel with the option enabled due to changes on struct
> >> kernel_symbol.
> >
> > Why would this be a problem?  Whenever making a kernel config change,
> > you should be able to rebuild everything, as lots of other configuration
> > options are that way.
> 
> This is not always true... there could be cases in which you cannot
> recompile old modules
> (e.g vendors that provide non GPL modules)

And breaking them is a feature.  I do not go out of my way to avoid breaking
out-of-tree modules; it's certainly more important to have simple maintainable
code.

You guys figure out what the best speed/size tradeoff is, and send me the
patch for review.

Thanks!
Rusty.