Reduce boot time console messages?

Woody Wu narkewoody at
Tue Aug 13 10:32:20 EDT 2013

On Mon, Aug 05, 2013 at 12:44:49AM -0400, Valdis.Kletnieks at wrote:
> On Mon, 05 Aug 2013 11:07:26 +0800, Woody Wu said:
> > Valdis, thank you very much.  I just passed loglevel=7 as kernel command
> > line and hope it can suspress KERN_DEBUG messages printed out to console
> > at boot time. But, it seems not work. A lot of debug level messages from
> > jffs2 module still print out. I will go to check where is wrong.
> Weird.  Do the "debugging" messages actually have the string '[JFFS2 DBG]'
> in them?  If not, then they're some *other* messages from jffs2.
> Also, double-check you don't have ignore_loglevel in the kernel command line.
> (This one can be tricky - do a 'cat /proc/cmdline' once you're booted to see
> what you really had - there's support for compiling in all/part of a commandline
> to work around buggy boot loaders that only support insanely short parameter
> lists - so what your  boot loader said it passed to the kernel may not be
> what the kernel used).

Sorry for such late reply.  Those dirty messages from jffs2 doesn't have
'[JFFS2 DBG]' or other prefixes.  Okay, I will look up the kernel source
again, to see if there are really KERN_DEBUG level. 

Btw: How can I know what command line parameters a module can
recogonize? I remember there is a definition to search in kernel .c


I can't go back to yesterday - because I was a different person then

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