Question

I put some debugging messages in the kernel code.
have checked /var/log/messages, dmesg and there is no such dump there.
syslogd is running on the machine

i also changed /proc/sys/kernel/printk to
8 4 1 7

any idea what can be the problem?

Answer 1

The easiest explanation is your printk() is not being called.

Keep it simple and stick to checking dmesg(1) output while you’re debugging this problem — all the syslog(3) /var/log/messages and the console based output are separate from the issue of the messages not even showing up in the kernel’s message buffer.