linux-kernel - Re: [PATCH v5 04/11] vsprintf: Do not check address of well-known strings

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Message-ID: <1524656669.21176.549.camel@linux.intel.com>
Date:   Wed, 25 Apr 2018 14:44:29 +0300
From:   Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
To:     Petr Mladek <pmladek@...e.com>,
        Rasmus Villemoes <linux@...musvillemoes.dk>
Cc:     Linus Torvalds <torvalds@...ux-foundation.org>,
        "Tobin C . Harding" <me@...in.cc>, Joe Perches <joe@...ches.com>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Michal Hocko <mhocko@...e.cz>,
        Sergey Senozhatsky <sergey.senozhatsky@...il.com>,
        Steven Rostedt <rostedt@...dmis.org>,
        Sergey Senozhatsky <sergey.senozhatsky.work@...il.com>,
        linux-kernel@...r.kernel.org
Subject: Re: [PATCH v5 04/11] vsprintf: Do not check address of well-known
 strings

On Wed, 2018-04-25 at 13:12 +0200, Petr Mladek wrote:
> We are going to check the address using probe_kernel_address(). It
> will
> be more expensive and it does not make sense for well known address.
> 
> This patch splits the string() function. The variant without the check
> is then used on locations that handle string constants or strings
> defined
> as local variables.
> 
> This patch does not change the existing behavior.

> -					buf = string(buf, end, ",",
> str_spec);

> +					buf = valid_string(buf, end,
> ",",
> +							   str_spec);

> -				return string(buf, end, "(invalid
> address)", spec);
> +				return valid_string(buf, end,
> +						    "(invalid
> address)", spec);
> 

I wouldn't give a crap about over 80 in above two cases. 

-- 
Andy Shevchenko <andriy.shevchenko@...ux.intel.com>
Intel Finland Oy