Re: [PATCH] printk: Monitor change of console loglevel.

[Joe Perches]

On Fri, 2019-05-24 at 10:17 -0700, Linus Torvalds wrote:
> > This patch is intended for testing on linux-next.git only, and
> > will be removed after we found what is wrong.
> 
> Honestly, wouldn't it be much better to try to come up with a patch
> that might be acceptable in general.
> 
> For example, how about a config option that just hardcodes
> console_loglevel as a compile-time constant, and where you can't
> change it at all? There are not that many paths that set the console
> log-level, and the few that do could be made to use
> 
>     set_console_log_level(x);
> 
> instead of
> 
>     console_loglevel = x;
> 
> like they do.
> 
> We already have a number of loglevel config options, adding another
> that says "fix log levels at compile time" doesn't sound too bad, and
> I suspect a patch that introduces that set_console_log_level() kind of
> model and just makes "console_loglevel" a constant #define wouldn't be
> too ugly.
> 
> A config option or two that help syzbot doesn't sound like a bad idea to me.
> 
> Hmm?

That could also help eliminate unnecessary pr_<foo> output
from object code.