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From:   Geert Uytterhoeven <geert@linux-m68k.org>
Date:   Wed, 8 Sep 2021 09:11:43 +0200
Message-ID: <CAMuHMdWhzL+aWosce71Xm-7dKsgXFyL42tQ2gV2HyEZp5r0N7A@mail.gmail.com>
Subject: Re: [PATCH] Enable '-Werror' by default for all kernel builds
To:     Guenter Roeck <linux@roeck-us.net>
Cc:     Al Viro <viro@zeniv.linux.org.uk>,
        Linus Torvalds <torvalds@linux-foundation.org>,
        "David S. Miller" <davem@davemloft.net>,
        Dmitry Torokhov <dmitry.torokhov@gmail.com>,
        Christian Koenig <christian.koenig@amd.com>,
        Huang Rui <ray.huang@amd.com>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        linux-sparc <sparclinux@vger.kernel.org>
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On Wed, Sep 8, 2021 at 7:16 AM Guenter Roeck <linux@roeck-us.net> wrote:
> On 9/7/21 9:48 PM, Al Viro wrote:
> > On Tue, Sep 07, 2021 at 09:28:38PM -0700, Guenter Roeck wrote:
> >>      memcpy(eth_addr, sanitize_address((void *) 0xfffc1f2c), ETH_ALEN);
> >>
> >> but that just seems weird. Is there a better solution ?
> >
> > (char (*)[ETH_ALEN])?  Said that, shouldn't that be doing something like
> > ioremap(), rather than casting explicit constants?
>
> Typecasts or even assigning the address to a variable does not help.
> The sanitizer function can not be static either.

So it can only be fixed by obfuscating the constant address in a
chain of out-of-line functions...
How is this compiler to be used for bare-metal programming?

> I don't know the hardware, so I can not answer the ioremap() question.

Yes it should.  But this driver dates back to 2.1.110, when only
half of the architectures already had ioremap().

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