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

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Message-ID: <xhsmh7cqgs51p.mognet@vschneid.remote.csb>
Date:   Mon, 31 Jul 2023 12:18:10 +0100
From:   Valentin Schneider <vschneid@...hat.com>
To:     Josh Poimboeuf <jpoimboe@...nel.org>
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Subject: Re: [RFC PATCH v2 12/20] objtool: Warn about non __ro_after_init
 static key usage in .noinstr

On 28/07/23 11:02, Josh Poimboeuf wrote:
> 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.
>

I had missed this, thanks for the pointer.

> --
> Josh