Re: [PATCH v2] printk: Add kernel parameter to disable writes to /dev/kmsg

From: Peter Zijlstra
Date: Tue Apr 26 2016 - 07:09:38 EST


On Tue, Apr 26, 2016 at 12:43:49PM +0200, Bjørn Mork wrote:
> Ingo Molnar <mingo@xxxxxxxxxx> writes:
>
> > static int parse_proc_cmdline_item(const char *key, const char *value) {
> >
> > /*
> > * The systemd.log_xyz= settings are parsed by all tools, and
> > * so is "debug".
> > *
> > * However, "quiet" is only parsed by PID 1, and only turns of
> > * status output to /dev/console, but does not alter the log
> > * level.
> > */
> >
> > if (streq(key, "debug") && !value)
> > log_set_max_level(LOG_DEBUG);
> >
> > else if (streq(key, "systemd.log_target") && value) {
> >
> > Why systemd does this fully knowing that other software (such as the kernel)
> > already uses 'debug', while systemd already has the 'system.*' parameter namespace
> > is left up to the reader...
>
> A couple of links to save that reader from making futile comments:
> https://lkml.org/lkml/2014/4/2/415
> https://bugs.freedesktop.org/show_bug.cgi?id=76935

Thanks for providing the links, I did remember all that.

Its one of the many reasons why I recommend against running
systemd(isease).