Re: [PATCH/RFC] m68k/amiga: Fix specifying multiple debug= parameters

[Geert Uytterhoeven]

On Thu, Oct 17, 2013 at 9:46 PM, Geert Uytterhoeven
<geert@xxxxxxxxxxxxxx> wrote:
> Since commit d6713b4091a99fa2af2fabdcd2f3fb97f32ecf2e ("m68k: early
> parameter support"), the user can specify multiple debug consoles using the
> "debug=" kernel command line parameter.
> However, as the struct console object was shared, it would actually register
> the same console object multiple times, causing the following warning:
>
> WARNING: CPU: 0 PID: 0 at kernel/printk/printk.c:2233 register_console+0x36/0x2b6()
> console 'debug0' already registered
>
> Note that only the console corresponding to the last "debug=" parameter became
> active, as the .write() method was overwritten before registration.
>
> Use separate console objects to allow using multiple debug consoles.
>
> Signed-off-by: Geert Uytterhoeven <geert@xxxxxxxxxxxxxx>
> ---
> Notes:
>   1. This patch was only compile-tested.
>   2. Do we want to fix it this way? Alternatives are:
>        a. Reject a second debug= parameter by checking for a non-NULL .write()
>           method
>           => only the first debug console will be used,
>        b. Skip console registration in case of a non-NULL .write() method
>           => only the last debug console will be used,
>   3. Atari has a similar issue, with even more (4) debug consoles.

No opinions?

Gr{oetje,eeting}s,

                        Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@xxxxxxxxxxxxxx

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
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