printk: allow setting DEFAULT_MESSAGE_LEVEL via Kconfig

We've been burned by regressions/bugs which we later realized could have been triaged quicker if only we'd paid closer attention to dmesg. To make it easier to audit dmesg, we'd like to make DEFAULT_MESSAGE_LEVEL Kconfig-settable. That way we can set it to KERN_NOTICE and audit any messages <= KERN_WARNING. Signed-off-by: Mandeep Singh Baines <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Joe Perches <[email protected]> Cc: Olof Johansson <[email protected]> Cc: Randy Dunlap <[email protected]> Signed-off-by: Andrew Morton <[email protected]> Signed-off-by: Linus Torvalds <[email protected]>
franciscofranco · Mar 23, 2011 · 5af5bcb · 5af5bcb
1 parent 9f36e2c
commit 5af5bcb
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diff --git a/kernel/printk.c b/kernel/printk.c
@@ -53,7 +53,7 @@ void asmlinkage __attribute__((weak)) early_printk(const char *fmt, ...)
 #define __LOG_BUF_LEN	(1 << CONFIG_LOG_BUF_SHIFT)
 
 /* printk's without a loglevel use this.. */
-#define DEFAULT_MESSAGE_LOGLEVEL 4 /* KERN_WARNING */
+#define DEFAULT_MESSAGE_LOGLEVEL CONFIG_DEFAULT_MESSAGE_LOGLEVEL
 
 /* We show everything that is MORE important than this.. */
 #define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */

diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
@@ -9,6 +9,17 @@ config PRINTK_TIME
 	  operations.  This is useful for identifying long delays
 	  in kernel startup.
 
+config DEFAULT_MESSAGE_LOGLEVEL
+	int "Default message log level (1-7)"
+	range 1 7
+	default "4"
+	help
+	  Default log level for printk statements with no specified priority.
+
+	  This was hard-coded to KERN_WARNING since at least 2.6.10 but folks
+	  that are auditing their logs closely may want to set it to a lower
+	  priority.
+
 config ENABLE_WARN_DEPRECATED
 	bool "Enable __deprecated logic"
 	default y