The log levels are:

Name

String

Meaning

alias function

KERN_EMERG

"0"

Emergency messages, system is about to crash or is unstable

pr_emerg

KERN_ALERT

"1"

Something bad happened and action must be taken immediately

pr_alert

KERN_CRIT

"2"

A critical condition occurred like a serious hardware/software failure

pr_crit

KERN_ERR

"3"

An error condition, often used by drivers to indicate difficulties with the hardware

pr_err

KERN_WARNING

"4"

A warning, meaning nothing serious by itself but might indicate problems

pr_warning

KERN_NOTICE

"5"

Nothing serious, but notably nevertheless. Often used to report security events.

pr_notice

KERN_INFO

"6"

Informational message e.g. startup information at driver initialization

pr_info

KERN_DEBUG

"7"

Debug messages

pr_debug, pr_devel if DEBUG is defined

KERN_DEFAULT

"d"

The default kernel loglevel


KERN_CONT

""

"continued" line of log printout (only done after a line that had no enclosing \n)

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pr_cont