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

From: Peter Zijlstra
Date: Mon Apr 25 2016 - 15:24:53 EST


On Mon, Apr 25, 2016 at 12:18:15PM -0700, Greg Kroah-Hartman wrote:
> On Mon, Apr 25, 2016 at 09:06:51PM +0200, Peter Zijlstra wrote:
> > On Mon, Apr 25, 2016 at 02:56:06PM -0400, Steven Rostedt wrote:
> > > +static bool __read_mostly devkmsg_disabled;
> > > +static int __init disable_devkmsg(char *str)
> > > +{
> > > + devkmsg_disabled = true;
> > > + return 0;
> > > +}
> > > +__setup("printk.disable_kmsg_write", disable_devkmsg);
> >
> > Again, please default enable and use an easier name to toggle this.
> > Userspace flooding this with junk is really insane.
>
> If you default enable, you break working systems today that want to log
> stuff through this interface, sorry.

Oh, you mean those 'working' systems that livelocked my box because I
had console to serial enabled which could not keep up with the endless
flood of shite?

This systemd exposure has seriously eroded your sanity.