Suppress kernel messages at startup without using quiet switch

yolkmeister · 04-04-2007, 09:11 PM

I have just compiled a custom 2.6.20.4 kernel for a specialized kernel that boots off of a tftp server (via PXE boot) to do ZENWorks imaging of operating systems for deployment of new computers. The kernel itself works perfectly for what I want it to do, but is more verbose than I would like it to be.

The problem - the kernel options that are passed are contained within a compressed file that requires a proprietary toolkit to change. The quiet option is not one of them, and I currently have no way to change this or pass the kernel any other options that are not currently specified.

The question - is there a way (possibly within the kernel itself) to suppress all the boot message when the kernel loads *without* passing boot options to it? I have searched and searched for a compile option, patch, anything that could do this but no luck so far. Does anyone have any insight on this? Thanks.

osor · 04-05-2007, 07:21 PM

Here’s a patch:

Code:

diff --git a/kernel/printk.c b/kernel/printk.c
--- a/kernel/printk.c
+++ b/kernel/printk.c
@@ -42,7 +42,7 @@
 
 /* We show everything that is MORE important than this.. */
 #define MINIMUM_CONSOLE_LOGLEVEL 1 /* Minimum loglevel we let people use */
-#define DEFAULT_CONSOLE_LOGLEVEL 7 /* anything MORE serious than KERN_DEBUG */
+#define DEFAULT_CONSOLE_LOGLEVEL 5 /* anything MORE serious than KERN_DEBUG */
 
 DECLARE_WAIT_QUEUE_HEAD(log_wait);

yolkmeister · 04-06-2007, 09:57 AM

Changing the default loglevel will do exactly what I want it do. From what I've read I can also change it back after boot with dmesg if required. I appreciate the help. Thanks.