[PATCH 0/8] Rework KERN_<LEVEL>

Andrew Morton akpm at linux-foundation.org
Tue Jun 5 20:46:38 EDT 2012


On Tue, 05 Jun 2012 17:40:05 -0700 Joe Perches <joe at perches.com> wrote:

> On Tue, 2012-06-05 at 17:37 -0700, Andrew Morton wrote:
> > On Tue, 05 Jun 2012 17:07:27 -0700 Joe Perches <joe at perches.com> wrote:
> > 
> > > On Tue, 2012-06-05 at 16:58 -0700, Andrew Morton wrote:
> > > >  echo "\0014Hello Joe" > /dev/kmsg
> > > 
> > > # echo -e "\x014Hello Me" > /dev/kmsg
> > > gives:
> > > 12,778,4057982669;Hello Me
> > 
> > That's changed behavior.
> 
> Which is an improvement too.

No it isn't.  It exposes internal kernel implementation details in
random weird inexplicable ways.  It doesn't seem at all important
though.

> I very much doubt a single app will change
> because of this.

I doubt it as well.

> > printk_emit() does parse the leading \0014, and then skips over it,
> > removing it from the output stream.  printk_emit() then throws away the
> > resulting level because devkmsg_writev() did not pass in level==-1.
> 
> I'm glad you know how it works now.

It's nice to see you learning about it as well.



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