Re: [RFC PATCH 2/2] livepatch: Clear relocation targets on a module removal

[Joe Lawrence]

On 9/2/19 12:13 PM, Miroslav Benes wrote:
> > I can easily foresee more problems like those in the future.  Going
> > forward we have to always keep track of which special sections are
> > needed for which architectures.  Those special sections can change over
> > time, or can simply be overlooked for a given architecture.  It's
> > fragile.
>
> Indeed. It bothers me a lot. Even x86 "port" is not feature complete in
> this regard (jump labels, alternatives,...) and who knows what lurks in
> the corners of the other architectures we support.
>
> So it is in itself reason enough to do something about late module
> patching.

Hi Miroslav,

I was tinkering with the "blue-sky" ideas that I mentioned to Josh the 
other day.  I dunno if you had a chance to look at what removing that 
code looks like, but I can continue to flesh out that idea if it looks 
interesting:

  https://github.com/joe-lawrence/linux/tree/blue-sky

A full demo would require packaging up replacement .ko's with a 
livepatch, as well as "blacklisting" those deprecated .kos, etc.  But 
that's all I had time to cook up last week before our holiday weekend here.

Regards,

-- Joe