Re: [PATCH] initrdscripts: add $CMDLINE to init-live switch_root

[ChenQi <Qi.Chen@windriver.com>]

On 01/15/2014 07:27 PM, krzysztof.m.sywula@intel.com wrote:
> From: Krzysztof Sywula <krzysztof.m.sywula@intel.com>
>
> init-live.sh: $CMDLINE variable should be provided to switch_root
> to let user specify runlevel on grub command line.
> Feeding with -c /dev/console as well as busybox switch_root enables that option.
>
> Signed-off-by: Krzysztof Sywula <krzysztof.m.sywula@intel.com>
> ---
>   meta/recipes-core/initrdscripts/files/init-live.sh | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
>
> diff --git a/meta/recipes-core/initrdscripts/files/init-live.sh b/meta/recipes-core/initrdscripts/files/init-live.sh
> index bd259b9..7e27f91 100644
> --- a/meta/recipes-core/initrdscripts/files/init-live.sh
> +++ b/meta/recipes-core/initrdscripts/files/init-live.sh
> @@ -89,7 +89,10 @@ boot_live_root() {
>       mount -n --move /dev ${ROOT_MOUNT}/dev
>   
>       cd $ROOT_MOUNT
> -    exec switch_root $ROOT_MOUNT /sbin/init
> +
> +    # busybox switch_root supports -c option
> +    exec switch_root -c /dev/console $ROOT_MOUNT /sbin/init $CMDLINE ||
> +        fatal "Couldn't switch_root, dropping to shell"
>   }
>   
>   fatal() {

I once sent out a patch to remove the '-c /dev/console' because this is 
busybox specific.
What if util-linux gets installed in the initramfs?

Could you please state what the benefit is with this option? Maybe in 
the comment?
The disadvantage is obvious, because if you have util-linux in 
initramfs, the 'switch_root' command doesn't support that option, and 
the 'switch_root' command would always fail.

Best Regards,
Chen Qi