Hi Christophe,

I love your patch! Yet something to improve:

[auto build test ERROR on powerpc/next]
[also build test ERROR on robh/for-next linus/master v5.12-rc1 next-20210302]
[cannot apply to mpe/next]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Christophe-Leroy/Improve-boot-command-line-handling/20210303-014039
base:   https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next
config: sh-randconfig-s031-20210302 (attached as .config)
compiler: sh4-linux-gcc (GCC) 9.3.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # apt-get install sparse
        # sparse version: v0.6.3-241-geaceeafa-dirty
        # https://github.com/0day-ci/linux/commit/edc3f8320d1dcb21a71e4cfdb26a3d2b64215c30
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Christophe-Leroy/Improve-boot-command-line-handling/20210303-014039
        git checkout edc3f8320d1dcb21a71e4cfdb26a3d2b64215c30
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=sh 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   arch/sh/Kconfig:760:warning: choice value used outside its choice group
>> init/Kconfig:142:error: recursive dependency detected!
   init/Kconfig:142: choice <choice> contains symbol CMDLINE
   init/Kconfig:132: symbol CMDLINE depends on CMDLINE_EXTEND
   init/Kconfig:155: symbol CMDLINE_EXTEND is part of choice <choice>
   For a resolution refer to Documentation/kbuild/kconfig-language.rst
   subsection "Kconfig recursive dependency limitations"


vim +142 init/Kconfig

   103	
   104	config BROKEN
   105		bool
   106	
   107	config BROKEN_ON_SMP
   108		bool
   109		depends on BROKEN || !SMP
   110		default y
   111	
   112	config INIT_ENV_ARG_LIMIT
   113		int
   114		default 32 if !UML
   115		default 128 if UML
   116		help
   117		  Maximum of each of the number of arguments and environment
   118		  variables passed to init from the kernel command line.
   119	
   120	config HAVE_CMDLINE
   121		bool
   122	
   123	config CMDLINE_BOOL
   124		bool "Default bootloader kernel arguments"
   125		depends on HAVE_CMDLINE
   126		help
   127		  On some platforms, there is currently no way for the boot loader to
   128		  pass arguments to the kernel. For these platforms, you can supply
   129		  some command-line options at build time by entering them here.  In
   130		  most cases you will need to specify the root device here.
   131	
   132	config CMDLINE
   133		string "Initial kernel command string"
   134		depends on CMDLINE_BOOL
   135		default DEFAULT_CMDLINE
   136		help
   137		  On some platforms, there is currently no way for the boot loader to
   138		  pass arguments to the kernel. For these platforms, you can supply
   139		  some command-line options at build time by entering them here.  In
   140		  most cases you will need to specify the root device here.
   141	
 > 142	choice
   143		prompt "Kernel command line type" if CMDLINE != ""
   144		default CMDLINE_FROM_BOOTLOADER
   145		help
   146		  Selects the way you want to use the default kernel arguments.
   147	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org