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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Tue, 14 May 2019 11:02:17 +0200
Message-ID: <CAMuHMdXaMObq9h2Sb49PW1-HUysPeaWXB7wJmKFz=xLmSoUDZg@mail.gmail.com>
Subject: Re: [PATCH] vsprintf: Do not break early boot with probing addresses
To:     David Laight <David.Laight@aculab.com>
Cc:     Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>,
        Petr Mladek <pmladek@suse.com>,
        Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
        christophe leroy <christophe.leroy@c-s.fr>,
        Steven Rostedt <rostedt@goodmis.org>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        Rasmus Villemoes <linux@rasmusvillemoes.dk>,
        "Tobin C . Harding" <me@tobin.cc>, Michal Hocko <mhocko@suse.cz>,
        Sergey Senozhatsky <sergey.senozhatsky@gmail.com>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        "linuxppc-dev@lists.ozlabs.org" <linuxppc-dev@lists.ozlabs.org>,
        Russell Currey <ruscur@russell.cc>,
        Stephen Rothwell <sfr@ozlabs.org>,
        Heiko Carstens <heiko.carstens@de.ibm.com>,
        "linux-arch@vger.kernel.org" <linux-arch@vger.kernel.org>,
        "linux-s390@vger.kernel.org" <linux-s390@vger.kernel.org>,
        Martin Schwidefsky <schwidefsky@de.ibm.com>
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On Tue, May 14, 2019 at 10:29 AM David Laight <David.Laight@aculab.com> wrote:
> > And I like Steven's "(fault)" idea.
> > How about this:
> >
> >       if ptr < PAGE_SIZE              -> "(null)"
> >       if IS_ERR_VALUE(ptr)            -> "(fault)"
> >
> >       -ss
>
> Or:
>         if (ptr < PAGE_SIZE)
>                 return ptr ? "(null+)" : "(null)";
>         if IS_ERR_VALUE(ptr)
>                 return "(errno)"

Do we care about the value? "(-E%u)"?

Gr{oetje,eeting}s,

                        Geert

-- 
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
                                -- Linus Torvalds