Hi,

I want to terminate kernel message printed on console via CONFIG_CMDLINE="rootfstype=squashfs,jffs2 noinitrd console=null" described in this wiki page:  wiki.openwrt.org/doc/recipes/terminate.console.on.serial

This config is located in target/linux/ar71xx/config-x.x. I change the file, and then use following commands:

make target/linux/clean
make target/linux/prepare
make

But there is no sign of "console=null" in build_dir/target-mips_34kc_uClibc-xx/linux-ar71xx_generic/linux-x.x.x/ when I use

grep -R "console=null"

The "CONFIG_CMDLINE" entry in target/linux/ar71xx/config-x.x is originally without console=null and it is just CONFIG_CMDLINE="rootfstype=squashfs,jffs2 noinitrd". This config (without console=null) is found in several files in the above mentioned build_dir path, like .config, .config.target, ar7_deconfig, but there is no sign of console=null in there.
Even when I change those files in build_dir manually and add console=null to them, after compiling it these changes become disappear and there is no sign of console=null again.
I have no  idea what is going on in here, and it has made me confused.

Any help will be greatly appreciated.

(Last edited by majid.it on 29 Oct 2016, 13:10)

Run 'touch' on the Makefile before the other commands you enter, then see if it does update?

thanks for reply,
I tested it but it had no result. When I run make kernel_menuconfig console=null appears in several files in build_dir but after make V=s all become disappeared again and kernel messages will be printed on console after changing firmware, thus I dont know whether the console=null is working or not.

I found the problem, there is a "config-default" file in target/linux/ar71xx/generic that the command CONFIG_CMDLINE="rootfstype=squashfs,jffs2 noinitrd" was written in it. so it replaced it with the everything in config-x.x. I commented that line and every thing goes well but it printed on screen anyway. So, I tried "loglevel=0" instead of "console=null" and it worked!!!!. Although, it prints some safe mode logs on console but it can be removed via commenting echo command in preinit files.