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Date:   Thu, 14 Jul 2022 09:18:12 +0200
From:   Peter Zijlstra <peterz@infradead.org>
To:     Josh Poimboeuf <jpoimboe@kernel.org>
Cc:     Kees Cook <keescook@chromium.org>,
        kernel test robot <oliver.sang@intel.com>, x86@kernel.org,
        Thomas Gleixner <tglx@linutronix.de>,
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        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] x86: Allow for exclusions in checking RETHUNK
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On Wed, Jul 13, 2022 at 04:55:56PM -0700, Josh Poimboeuf wrote:
> Here's the ANNOTATE_UNSAFE_RET idea.

Right, I suppose that strictly speaking the compiler can do whatever and
there's no actual guarantee the annotation hits the RET instruction, in
practise it should work, esp. since noinstr.

> Most of the diff is moving the
> annotation macros to objtool.h (where they belong anyway).

Yeah, moving those is a good idea.