Re: [PATCH] kernel/trace: Add TRACING_ALLOW_PRINTK config option

[Steven Rostedt]

On Wed, 24 Jun 2020 16:45:24 +0800
Nicolas Boichat <drinkcat@xxxxxxxxxxxx> wrote:

> trace_printk is only meant as a debugging tool, and should never be
> compiled into production code without source code changes, as
> indicated by the warning that shows up on boot if any trace_printk
> is called:
>  **   NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE NOTICE   **
>  **                                                      **
>  ** trace_printk() being used. Allocating extra memory.  **
>  **                                                      **
>  ** This means that this is a DEBUG kernel and it is     **
>  ** unsafe for production use.                           **
> 
> If this option is set to n, the kernel will generate a build-time
> error if trace_printk is used.
> 
> Signed-off-by: Nicolas Boichat <drinkcat@xxxxxxxxxxxx>

Interesting. Note, this will prevent modules with trace_printk from
being loaded as well.

-- Steve