Re: [PATCH] killswitch: add per-function short-circuit mitigation primitive

[Andrew Morton <akpm@linux-foundation.org>]

On Mon, 11 May 2026 15:07:51 +0200 Michal Hocko <mhocko@suse.com> wrote:

> > 2) It's common to run hundreds of different kernel versions across a
> >    fleet. Since livepatch is kernel-specific, a single CVE suddenly
> >    requires building and deploying hundreds of individual livepatches—
> >    far less practical than a simple sysfs write.
> 
> LP is certainly a more laborous solution.

<another please-educate-akpm email>

Does a livepatch *have* to be distributed as a ready-to-load kernel
module?

Is it not possible to distribute a "livepatch" to the fleet as a single
string?  Send out "make function some_bad_function() return -EINVAL"
and let scripting on each machine figure out how to locally write,
build, sign and install such a livepatch?

That would require that each machine locally contains enough data for
it to be able to build a kernel for the currently-running kernel, and
that each machine contains a build environment.

I *think* this is feasible on distro-based machines?  But perhaps not
on stripped-down hyperscalar boxen?