On Wed, Mar 31, 2021 at 11:59 AM Geert Uytterhoeven
<geert+renesas@xxxxxxxxx> wrote:
> While long fancy messages have a higher probability of being seen than
> small messages, they may scroll of the screen fast, if visible at all,
> and may still be missed. In addition, they increase boot time and
> kernel size.
>
> The correct mechanism to increase importance of a kernel message is not
> to draw fancy boxes with more text, but to shout louder, i.e. increase
> the message's reporting level. Making sure the administrator of the
> system is aware of such a message is a system policy, and is the
> responsability of a user-space log daemon.
>
> Fix this by increasing the reporting level from KERN_WARNING to
> KERN_CRIT, and removing irrelevant text and graphics.
>
> This reduces kernel size by ca. 0.5 KiB.
>
> Fixes: 5ead723a20e0447b ("lib/vsprintf: no_hash_pointers prints all addresses as unhashed")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@xxxxxxxxx>
No comments?
Unlike the cases handled by the other two patches in this series,
this one cannot be configured out.
Thanks!
> --- a/lib/vsprintf.c
> +++ b/lib/vsprintf.c
> @@ -2193,20 +2193,9 @@ static int __init no_hash_pointers_enable(char *str)
>
> no_hash_pointers = true;
>
> - pr_warn("**********************************************************\n");
> - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
> - pr_warn("** **\n");
> - pr_warn("** This system shows unhashed kernel memory addresses **\n");
> - pr_warn("** via the console, logs, and other interfaces. This **\n");
> - pr_warn("** might reduce the security of your system. **\n");
> - pr_warn("** **\n");
> - pr_warn("** If you see this message and you are not debugging **\n");
> - pr_warn("** the kernel, report this immediately to your system **\n");
> - pr_warn("** administrator! **\n");
> - pr_warn("** **\n");
> - pr_warn("** NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE **\n");
> - pr_warn("**********************************************************\n");
> -
> + pr_crit("This system shows unhashed kernel memory addresses\n");
> + pr_crit("via the console, logs, and other interfaces. This\n");
> + pr_crit("might reduce the security of your system.\n");
> return 0;
> }
> early_param("no_hash_pointers", no_hash_pointers_enable);
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
