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Date:   Mon, 8 Feb 2021 20:48:54 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     "Yu, Yu-cheng" <yu-cheng.yu@intel.com>
Cc:     x86@kernel.org, "H. Peter Anvin" <hpa@zytor.com>,
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Subject: Re: [PATCH v19 06/25] x86/cet: Add control-protection fault handler
Message-ID: <20210208194854.GI18227@zn.tnic>
References: <20210203225547.32221-1-yu-cheng.yu@intel.com>
 <20210203225547.32221-7-yu-cheng.yu@intel.com>
 <20210205135927.GH17488@zn.tnic>
 <2d829cba-784e-635a-e0c5-a7b334fa9b40@intel.com>
 <20210208182009.GE18227@zn.tnic>
 <690bc3b9-2890-e68d-5e4b-cda5c21b496b@intel.com>
 <20210208185341.GF18227@zn.tnic>
 <0e0c9e9d-aee1-ad1e-6c63-21b58a52163f@intel.com>
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On Mon, Feb 08, 2021 at 11:23:18AM -0800, Yu, Yu-cheng wrote:
> exc_general_protection() and do_trap() both call show_signal(), which
> then calls printk_ratelimit().

You could've done some git archeology and could've found

  abd4f7505baf ("x86: i386-show-unhandled-signals-v3")

which explains why that ratelimiting is needed.

> For example, if a shell script, in a loop re-starts an app when it
> exits, and the app is causing control-protection fault. The log
> messages should be rate limited.

I think you should be able to get where I'm going with this, by now:
please put a comment over the ratelimiting to explain why it is there,
just like the above commit explains.

Thx.

-- 
Regards/Gruss,
    Boris.

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