Re: [PATCH next v3 07/15] printk: introduce CONSOLE_LOG_MAX for improved multi-line support

From: Geert Uytterhoeven
Date: Tue Mar 02 2021 - 11:30:30 EST


Hi John,

On Thu, Feb 25, 2021 at 9:30 PM John Ogness <john.ogness@xxxxxxxxxxxxx> wrote:
> Instead of using "LOG_LINE_MAX + PREFIX_MAX" for temporary buffer
> sizes, introduce CONSOLE_LOG_MAX. This represents the maximum size
> that is allowed to be printed to the console for a single record.
>
> Rather than setting CONSOLE_LOG_MAX to "LOG_LINE_MAX + PREFIX_MAX"
> (1024), increase it to 4096. With a larger buffer size, multi-line
> records that are nearly LOG_LINE_MAX in length will have a better
> chance of being fully printed. (When formatting a record for the
> console, each line of a multi-line record is prepended with a copy
> of the prefix.)
>
> Signed-off-by: John Ogness <john.ogness@xxxxxxxxxxxxx>
> Reviewed-by: Petr Mladek <pmladek@xxxxxxxx>

Thanks for your patch!

This increases kernel size by more than 3 KiB, which affects small
devices (e.g. SoCs with 10 MiB of SRAM inside).
Who is printing such long lines to the console?

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