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Date:   Tue, 18 Oct 2022 22:22:15 -0700
From:   Kees Cook <keescook@chromium.org>
To:     Josh Poimboeuf <jpoimboe@kernel.org>
Cc:     Peter Zijlstra <peterz@infradead.org>, x86@kernel.org,
        Sami Tolvanen <samitolvanen@google.com>,
        Joao Moreira <joao@overdrivepizza.com>,
        linux-kernel@vger.kernel.org, Mark Rutland <mark.rutland@arm.com>,
        Josh Poimboeuf <jpoimboe@redhat.com>
Subject: Re: [PATCH] x86/ibt: Implement FineIBT
Message-ID: <202210182220.B6247EF@keescook>
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On Tue, Oct 18, 2022 at 04:31:48PM -0700, Josh Poimboeuf wrote:
> Is there a reason not to default to FineIBT if the hardware supports it?

I think it's a fine default. Given the behavioral differences, though,
I'd like to make it configurable.

> If we're going to give the user choices then my previous rant about
> documentation still applies:
> 
>   https://lkml.kernel.org/lkml/20220503220244.vyz5flk3gg3y6rbw@treble

Totally agreed. I would be happy to pen something if no one else is
interested.

-- 
Kees Cook