Re: [RFC 00/31] objtool, livepatch: Livepatch module generation

From: Josh Poimboeuf
Date: Wed Sep 11 2024 - 03:39:53 EST


On Mon, Sep 02, 2024 at 08:59:43PM -0700, Josh Poimboeuf wrote:
> Hi,
>
> Here's a new way to build livepatch modules called klp-build.
>
> I started working on it when I realized that objtool already does 99% of
> the work needed for detecting function changes.
>
> This is similar in concept to kpatch-build, but the implementation is
> much cleaner.
>
> Personally I still have reservations about the "source-based" approach
> (klp-convert and friends), including the fragility and performance
> concerns of -flive-patching. I would submit that klp-build might be
> considered the "official" way to make livepatch modules.
>
> Please try it out and let me know what you think. Based on v6.10.
>
> Also avaiable at:
>
> git://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git klp-build-rfc

Here's an updated branch with a bunch of fixes. It's still incompatible
with BTF at the moment, otherwise it should (hopefully) fix the rest of
the issues reported so far.

While the known bugs are fixed, I haven't finished processing all the
review comments yet. Once that happens I'll post a proper v2.

git://git.kernel.org/pub/scm/linux/kernel/git/jpoimboe/linux.git klp-build-v1.5

--
Josh