linux-kernel - Re: [RFC PATCH v2 12/20] objtool: Warn about non __ro_after

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Message-ID: <20230728160247.multb2csnpa22fgx@treble>
Date:   Fri, 28 Jul 2023 11:02:47 -0500
From:   Josh Poimboeuf <jpoimboe@...nel.org>
To:     Valentin Schneider <vschneid@...hat.com>
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Subject: Re: [RFC PATCH v2 12/20] objtool: Warn about non __ro_after_init
 static key usage in .noinstr

On Thu, Jul 20, 2023 at 05:30:48PM +0100, Valentin Schneider wrote:
> Later commits will depend on having no runtime-mutable text in early entry
> code. (ab)use the .noinstr section as a marker of early entry code and warn
> about static keys used in it that can be flipped at runtime.

Similar to my comment on patch 13, this could also use a short
justification for adding the feature, i.e. why runtime-mutable text
isn't going to be allowed in .noinstr.

Also, please add a short description of the warning (and why it exists)
to tools/objtool/Documentation/objtool.txt.

-- 
Josh