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Date:   Thu, 10 Mar 2022 15:27:58 +0100
From:   Peter Zijlstra <peterz@infradead.org>
To:     David Laight <David.Laight@aculab.com>
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Subject: Re: [PATCH v4 00/45] x86: Kernel IBT
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On Wed, Mar 09, 2022 at 01:37:50PM +0000, David Laight wrote:
> I'm wondering what actually happens to loadable modules?

They work just fine..

> Especially those built 'out of tree',
> potentially with a different compiler,
> and maybe containing binary 'blobs'.

-EDONTCARE, you're on your own and get to keep whatever pieces.
In fact, the more pieces I can get you, the better I feel about it.

> The requirement to run programs on old distributions means
> that things get compiled with quite old versions of gcc.
> For instance RHEL7 is gcc 4.8.5.

Min GCC is 5.1. If you want Kernel IBT you get to use GCC-9 (or 8 with
backports) but I'd recommend using GCC-10 or later since before that the
IBT code-gen is pretty stupid.

If you build modules using another compiler than the main kernel, you
again get to keep the pieces.