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Date:   Thu, 30 Sep 2021 13:49:22 +0200
From:   Borislav Petkov <bp@alien8.de>
To:     Lai Jiangshan <jiangshanlai@gmail.com>
Cc:     linux-kernel@vger.kernel.org,
        Lai Jiangshan <laijs@linux.alibaba.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Juergen Gross <jgross@suse.com>,
        "Peter Zijlstra (Intel)" <peterz@infradead.org>,
        Joerg Roedel <jroedel@suse.de>,
        Mike Travis <mike.travis@hpe.com>
Subject: Re: [PATCH V2 04/41] x86/entry: Introduce __entry_text for entry
 code written in C
Message-ID: <YVWkQgQD+j9fT6Ge@zn.tnic>
References: <20210926150838.197719-1-jiangshanlai@gmail.com>
 <20210926150838.197719-5-jiangshanlai@gmail.com>
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On Sun, Sep 26, 2021 at 11:08:01PM +0800, Lai Jiangshan wrote:
> From: Lai Jiangshan <laijs@linux.alibaba.com>
> 
> Some entry code will be implemented in C files.  We need __entry_text

Who's "we"?

> to set them in .entry.text section.  __entry_text disables instruments

s/instruments/instrumentation/

> like noinstr, but it doesn't disable stack protector since not all
> compiler supported by kernel supporting function level granular
> attribute to disable stack protector.  It will be disabled by C file
> level.
> 
> Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
> ---
>  arch/x86/include/asm/idtentry.h | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/arch/x86/include/asm/idtentry.h b/arch/x86/include/asm/idtentry.h
> index 1345088e9902..6779def97591 100644
> --- a/arch/x86/include/asm/idtentry.h
> +++ b/arch/x86/include/asm/idtentry.h
> @@ -11,6 +11,9 @@
>  
>  #include <asm/irq_stack.h>
>  
> +/* Entry code written in C. */
> +#define __entry_text __noinstr_section(".entry.text")

I'm assuming that __noinstr_section() is defined somewhere, maybe in
patch 3, which I don't have in my mbox.

Yah, the 0th message says:

"  compiler_types.h: Add __noinstr_section() for noinstr"

Aha, I see why: you haven't CCed me on that one so I don't have it:

https://lkml.kernel.org/r/20210926150838.197719-4-jiangshanlai@gmail.com

I have all the remaining 40 but not that one.

On your next submission, please make sure you CC x86@kernel.org so that
all x86 people get the whole patchset.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette