From mboxrd@z Thu Jan  1 00:00:00 1970
From: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Subject: Re: [PATCH V11 4/5] vsprintf: add printk specifier %px
Date: Thu, 7 Dec 2017 14:37:55 +0900
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Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Geert Uytterhoeven <geert@linux-m68k.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Randy Dunlap <rdunlap@infradead.org>,
        David Laight <David.Laight@aculab.com>,
        Kees Cook <keescook@chromium.org>,
        "kernel-hardening@lists.openwall.com"
        <kernel-hardening@lists.openwall.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        Theodore Ts'o <tytso@mit.edu>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Tycho Andersen <tycho@tycho.ws>,
        "Roberts, William C" <william.c.roberts@intel.com>,
        Tejun Heo <tj@kernel.org>,
        Jordan Glover <Golden_Miller83@protonmail.ch>,
        Greg KH <gregkh@linuxfoundation.org>,
        Petr Mladek <pmladek@suse.com>, Joe Perches <joe@perches.com>,
        Ian Campbell <ijc@hellion.org.uk>,
        Sergey Seno
To: "Tobin C. Harding" <me@tobin.cc>
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On (12/07/17 16:17), Tobin C. Harding wrote:
[..]
> > hm, indeed. and !CONFIG_KALLSYMS config turns %pS/%ps
> > into special_hex_number().
> 
> But totally misses this :(
> 
> "<no-sym>" would be better returned when !CONFIG_KALLSYMS, right?

I guess I'll take back my comment.

I assume there are tons of embedded devices that have !CONFIG_KALLSYMS
in 'release' builds, yet those devices still warn/oops sometimes; having
pointers/hex numbers is really the only way to make any sense out of
backtraces... yet it, basically, means that we are leaking kernel pointers.

	-ss