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

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

On 05/15/2014 02:29 PM, ChenQi wrote:
> 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

ping