Re: [PATCH v2 2/3] lockdown/kunit: Introduce kunit tests

[Nikolay Borisov <nik.borisov@suse.com>]

On 29.07.25 г. 1:04 ч., kernel test robot wrote:
> Hi Nikolay,
> 
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on linus/master]
> [also build test WARNING on v6.16 next-20250728]
> [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/Nikolay-Borisov/lockdown-Switch-implementation-to-using-bitmap/20250728-191807
> base:   linus/master
> patch link:    https://lore.kernel.org/r/20250728111517.134116-3-nik.borisov%40suse.com
> patch subject: [PATCH v2 2/3] lockdown/kunit: Introduce kunit tests
> config: arm-randconfig-004-20250729 (https://download.01.org/0day-ci/archive/20250729/202507290540.9IANrMED-lkp@intel.com/config)
> compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 1b4db78d2eaa070b3f364a2d2b2b826a5439b892)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250729/202507290540.9IANrMED-lkp@intel.com/reproduce)
> 
> If you fix the issue in a separate patch/commit (i.e. not just a new version of
> the same patch/commit), kindly add following tags
> | Reported-by: kernel test robot <lkp@intel.com>
> | Closes: https://lore.kernel.org/oe-kbuild-all/202507290540.9IANrMED-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>>> security/lockdown/lockdown.c:31:5: warning: no previous prototype for function 'lock_kernel_down' [-Wmissing-prototypes]
>        31 | int lock_kernel_down(const char *where, enum lockdown_reason level)
>           |     ^
>     security/lockdown/lockdown.c:31:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
>        31 | int lock_kernel_down(const char *where, enum lockdown_reason level)
>           | ^
>           | static
>     1 warning generated.


That's a false positive, since the function is exported only for KUNIT 
case, what's the correct way to make testbot ignore it ?
> 
> 
> vim +/lock_kernel_down +31 security/lockdown/lockdown.c
> 
>      20	
>      21	static const enum lockdown_reason lockdown_levels[] = {LOCKDOWN_NONE,
>      22							 LOCKDOWN_INTEGRITY_MAX,
>      23							 LOCKDOWN_CONFIDENTIALITY_MAX};
>      24	
>      25	/*
>      26	 * Put the kernel into lock-down mode.
>      27	 */
>      28	#if !IS_ENABLED(CONFIG_KUNIT)
>      29	static
>      30	#endif
>    > 31	int lock_kernel_down(const char *where, enum lockdown_reason level)
>      32	{
>      33	
>      34		if (level > LOCKDOWN_CONFIDENTIALITY_MAX)
>      35			return -EINVAL;
>      36	
>      37		if (level == LOCKDOWN_INTEGRITY_MAX || level == LOCKDOWN_CONFIDENTIALITY_MAX)
>      38			bitmap_set(kernel_locked_down, 1, level);
>      39		else
>      40			bitmap_set(kernel_locked_down, level, 1);
>      41	
>      42		pr_notice("Kernel is locked down from %s; see man kernel_lockdown.7\n",
>      43			  where);
>      44		return 0;
>      45	}
>      46	
>