Re: [PATCH] efivarfs: fix NULL-deref on mount when no efivars

[kernel test robot <lkp@intel.com>]

Hi Johan,

I love your patch! Yet something to improve:

[auto build test ERROR on v6.2-rc5]
[also build test ERROR on linus/master]
[cannot apply to efi/next next-20230223]
[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#_base_tree_information]

url:    https://github.com/intel-lab-lkp/linux/commits/Johan-Hovold/efivarfs-fix-NULL-deref-on-mount-when-no-efivars/20230128-094525
patch link:    https://lore.kernel.org/r/20230126112129.4602-1-johan%2Blinaro%40kernel.org
patch subject: [PATCH] efivarfs: fix NULL-deref on mount when no efivars
config: i386-randconfig-a015 (https://download.01.org/0day-ci/archive/20230223/202302231733.iymwHTPf-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/intel-lab-lkp/linux/commit/da57163cc9d947884520240ec71c2806f48b8a64
        git remote add linux-review https://github.com/intel-lab-lkp/linux
        git fetch --no-tags linux-review Johan-Hovold/efivarfs-fix-NULL-deref-on-mount-when-no-efivars/20230128-094525
        git checkout da57163cc9d947884520240ec71c2806f48b8a64
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash fs/

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202302231733.iymwHTPf-lkp@intel.com/

All errors (new ones prefixed by >>):

>> fs/efivarfs/super.c:246:7: error: implicit declaration of function 'efivar_is_available' is invalid in C99 [-Werror,-Wimplicit-function-declaration]
           if (!efivar_is_available())
                ^
   fs/efivarfs/super.c:246:7: note: did you mean 'slab_is_available'?
   include/linux/slab.h:171:6: note: 'slab_is_available' declared here
   bool slab_is_available(void);
        ^
   1 error generated.


vim +/efivar_is_available +246 fs/efivarfs/super.c

   241	
   242	static void efivarfs_kill_sb(struct super_block *sb)
   243	{
   244		kill_litter_super(sb);
   245	
 > 246		if (!efivar_is_available())
   247			return;
   248	
   249		/* Remove all entries and destroy */
   250		efivar_entry_iter(efivarfs_destroy, &efivarfs_list, NULL);
   251	}
   252	

-- 
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests