linux-kernel - Re: [PATCH 0/3] x86/mce: Fix more noinstr fun

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Fri, 4 Feb 2022 12:24:00 +0100
From:   Marco Elver <elver@...gle.com>
To:     Borislav Petkov <bp@...en8.de>
Cc:     Tony Luck <tony.luck@...el.com>, Jakub Kicinski <kuba@...nel.org>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        X86 ML <x86@...nel.org>, LKML <linux-kernel@...r.kernel.org>
Subject: Re: [PATCH 0/3] x86/mce: Fix more noinstr fun

On Fri, 4 Feb 2022 at 09:30, Borislav Petkov <bp@...en8.de> wrote:
>
> From: Borislav Petkov <bp@...e.de>
>
> Hi all,
>
> here's a second small set of fixes for objtool noinstr validation issues
> in the MCE code.
>
> It goes ontop of tip:locking/core where there are some more commits
> changing generic helpers to be always inlined.
>
> As always, comments and suggestions are appreciated.
>
> Thx.
>
> Borislav Petkov (3):
>   cpumask: Add a x86-specific cpumask_clear_cpu() helper
>   x86/ptrace: Always inline v8086_mode() for instrumentation
>   x86/mce: Use arch atomic and bit helpers

I guess to solve noinstr "calling" something else the only solution is
to make the other function noinstr as well, or __always_inline.

Have you considered making some of these other functions 'noinstr' as
well? I guess __always_inline works, esp. if there's just 1 caller.
And by the looks of it you're getting a net .text reduction, so

Acked-by: Marco Elver <elver@...gle.com>