Hide boot on-screen errors, or get TV-out working on ATI Radeon X300

Tom H tomh0665 at gmail.com
Mon Dec 8 11:27:22 UTC 2014

On Mon, Dec 8, 2014 at 6:04 AM, Tom H <tomh0665 at gmail.com> wrote:
> If you're not on 15.04, you can get the latest man-pages (manpages in
> Ubuntu) from
> https://www.kernel.org/pub/linux/docs/man-pages/
> untar it, and run "man man-pages-3.75/man2/syslog.2"

Forgot to include the relevant section from the man page above:

       /proc/sys/kernel/printk is a writable file containing four
integer values that influence kernel printk() behavior when printing
or logging error messages.  The four values are:

              Only messages with a log level lower than this value
will be printed to the console.  The default value for this field is
DEFAULT_CONSOLE_LOGLEVEL (7), but it is set to 4 if the kernel command
line contains the word
              "quiet", 10 if the kernel command line contains the word
"debug", and to 15 in case of a kernel fault (the 10 and 15 are just
silly, and equivalent to 8).  The value of console_loglevel can be set
(to a value in the
              range 1-8) by a syslog() call with a type of 8.

              This value will be used as the log level for printk()
messages that do not have an explicit level.  Up to and including
Linux 2.6.38, the hard-coded default value for this field was  4
(KERN_WARNING);  since  Linux
              2.6.39, the default value is a defined by the kernel
configuration option CONFIG_DEFAULT_MESSAGE_LOGLEVEL, which defaults
to 4.

              The value in this field is the minimum value to which
console_loglevel can be set.

              This is the default value for console_loglevel.

   The log level
       Every printk() message has its own log level.  If the log level
is not explicitly specified as part of the message, it defaults to
default_message_loglevel.  The conventional meaning of the log level
is as follows:

       Kernel constant   Level value   Meaning
       KERN_EMERG             0        System is unusable
       KERN_ALERT             1        Action must be taken immediately
       KERN_CRIT              2        Critical conditions
       KERN_ERR               3        Error conditions
       KERN_WARNING           4        Warning conditions
       KERN_NOTICE            5        Normal but significant condition
       KERN_INFO              6        Informational
       KERN_DEBUG             7        Debug-level messages

       The kernel printk() routine will print a message on the console
only if it has a log level less than the value of console_loglevel.

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