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Subject: Re: [PATCH][RESEND] lib/vsprintf: make-printk-non-secret printks all
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To:     Steven Rostedt <rostedt@goodmis.org>,
        Kees Cook <keescook@chromium.org>
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        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        akinobu.mita@gmail.com
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From:   Timur Tabi <timur@kernel.org>
Message-ID: <a6556624-71d5-e689-5273-693c69c77c9e@kernel.org>
Date:   Wed, 3 Feb 2021 15:56:20 -0600
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On 2/3/21 2:47 PM, Steven Rostedt wrote:
>   static void __init
>   plain(void)
>   {
>   	int err;
>   
> +	if (debug_never_hash_pointers)
> +		return;

So, I have a stupid question.  What's the best way for test_printf.c to 
read the command line parameter?  Should I just do this in vsprintf.c:

/* Disable pointer hashing if requested */
static bool debug_never_hash_pointers __ro_after_init;
EXPORT_SYMBOL_GPL(debug_never_hash_pointers);

I'm not crazy about exporting this variable to other drivers.  It could 
be used to disable hashing by any driver.

AFAIK, the only command-line parameter code that works in drivers is 
module_parm, and that expects the module prefix on the command-line.