Re: [PATCH v6 3/4] printk: Userspace format indexing support

From: Chris Down <chris@chrisdown.name>
To: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: linux-kernel@vger.kernel.org, Petr Mladek <pmladek@suse.com>,
	Jessica Yu <jeyu@kernel.org>,
	Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
	John Ogness <john.ogness@linutronix.de>,
	Steven Rostedt <rostedt@goodmis.org>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	Johannes Weiner <hannes@cmpxchg.org>,
	Kees Cook <keescook@chromium.org>,
	Rasmus Villemoes <linux@rasmusvillemoes.dk>,
	kernel-team@fb.com
Subject: Re: [PATCH v6 3/4] printk: Userspace format indexing support
Date: Tue, 18 May 2021 17:59:23 +0100	[thread overview]
Message-ID: <YKPyaw0bt+e/BhnR@chrisdown.name> (raw)
In-Reply-To: <YKPrGr71Xp99oh0u@chrisdown.name>

Chris Down writes:
>Andy Shevchenko writes:
>>>As for the literals, are you saying that you prefer that it's symbolised as
>>>a macro or static char, or do you know of an API where this kind of name can
>>>be canonically accessed?
>>
>>I have heard that modern GCC (at least) can utilize same constant literals in a
>>single compilation unit, so it won't be duplicated.
>>
>>But more serious here is the guarantees of the name. Shouldn't it come from
>>KBuild / Makefile into some header like version do?
>
>I'm not against that, but it seems like something worth doing outside 
>of this patch series, unless you have strong feelings to the contrary?
>
>More than happy to put that on my TODO list for tree-wide cleanups.

Now I think about it, we even just call it that in struct module's is_vmlinux, 
and set that by doing `strcmp(modname, "vmlinux") == 0`, so it seems pretty 
static from a terminology point of view.

It would be nice to just always use `mod->name`, but unfortunately with 
!CONFIG_MODULES we don't have `struct module` fleshed out at all in order to do 
so.