Re: [PATCH 3/3] [v4] lib/vsprintf: no_hash_pointers prints all addresses as unhashed

Steven Rostedt
2021-03-02T16:30:33Z

On Tue, 2 Mar 2021 14:49:42 +0100
Geert Uytterhoeven <geert@linux-m68k.org> wrote:

> > So this is basically a kernel tinyfication issue, right? Is that still pursued
> > today? Are there better config options suitable for this than CONFIG_DEBUG_KERNEL?
>
> As long as I hear about products running Linux on SoCs with 10 MiB of
> SRAM, I think the answer is yes.
> I'm not immediately aware of a better config option. There are no more
> TINY options left, and EXPERT selects DEBUG_KERNEL.

Since the trace_printk() uses the same type of notice, I wonder if we could
make this into a helper function and just pass in the top part.

+ 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");

Only the above section is really unique. The rest can be a boiler plate.

-- Steve

+ 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");
+