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Date: Fri, 8 May 2026 17:36:21 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Sasha Levin <sashal@kernel.org>
Cc: corbet@lwn.net, skhan@linuxfoundation.org, linux-doc@vger.kernel.org,
 linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org,
 gregkh@linuxfoundation.org
Subject: Re: [PATCH] killswitch: add per-function short-circuit mitigation
 primitive
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On Fri, 8 May 2026 20:15:00 -0400 Sasha Levin <sashal@kernel.org> wrote:

> Livepatch is great when you have one. The problem is getting one...
> 
> To get a livepatch, somebody has to write the fix, build it against the exact
> kernel you're running (for distros, thats hundreds of different
> kernel/arch/flavor combinations), sign it, and get it onto every machine.
> 
> Most regular users won't be able to do it on their own because of secure boot
> limitations, so they depend on their vendor to provide them with one.
> 
> Yes, you could write a livepatch that just stubs the function out, same end
> state as killswitch, but you still have to build, sign, and ship a module per
> kernel to do it
> 
> Killswitch would be just a single write to /sys which an ordinary user can do
> to mitigate a critical issue immediately.

OK, thanks.  Worth adding the changelog in case someone else was
wondering?