Re: [PATCH] mm/kmemleak: Avoid scanning potential huge holes

[kernel test robot]

Hi Lang,

Thank you for the patch! Yet something to improve:

[auto build test ERROR on hnaz-mm/master]

url:    https://github.com/0day-ci/linux/commits/Lang-Yu/mm-kmemleak-Avoid-scanning-potential-huge-holes/20211105-115425
base:   https://github.com/hnaz/linux-mm master
config: xtensa-allyesconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 11.2.0
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/0day-ci/linux/commit/d455f236523de8c6b91774a74eb3163d2ff16e2e
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Lang-Yu/mm-kmemleak-Avoid-scanning-potential-huge-holes/20211105-115425
        git checkout d455f236523de8c6b91774a74eb3163d2ff16e2e
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=xtensa 

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

All errors (new ones prefixed by >>):

   mm/kmemleak.c: In function 'kmemleak_scan':
>> mm/kmemleak.c:1407:13: error: unused variable 'i' [-Werror=unused-variable]
    1407 |         int i;
         |             ^
   cc1: all warnings being treated as errors


vim +/i +1407 mm/kmemleak.c

04609ccc40c4e8 Catalin Marinas 2009-10-28  1396  
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1397  /*
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1398   * Scan data sections and all the referenced memory blocks allocated via the
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1399   * kernel's standard allocators. This function must be called with the
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1400   * scan_mutex held.
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1401   */
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1402  static void kmemleak_scan(void)
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1403  {
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1404  	unsigned long flags;
04609ccc40c4e8 Catalin Marinas 2009-10-28  1405  	struct kmemleak_object *object;
d455f236523de8 Lang Yu         2021-11-05  1406  	struct zone *zone;
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11 @1407  	int i;
4698c1f2bbe44c Catalin Marinas 2009-06-26  1408  	int new_leaks = 0;
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1409  
acf4968ec9dea4 Catalin Marinas 2009-06-26  1410  	jiffies_last_scan = jiffies;
acf4968ec9dea4 Catalin Marinas 2009-06-26  1411  
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1412  	/* prepare the kmemleak_object's */
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1413  	rcu_read_lock();
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1414  	list_for_each_entry_rcu(object, &object_list, object_list) {
8c96f1bc6fc49c He Zhe          2020-01-30  1415  		raw_spin_lock_irqsave(&object->lock, flags);
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1416  #ifdef DEBUG
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1417  		/*
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1418  		 * With a few exceptions there should be a maximum of
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1419  		 * 1 reference to any object at this point.
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1420  		 */
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1421  		if (atomic_read(&object->use_count) > 1) {
ae281064be1643 Joe Perches     2009-06-23  1422  			pr_debug("object->use_count = %d\n",
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1423  				 atomic_read(&object->use_count));
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1424  			dump_object_info(object);
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1425  		}
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1426  #endif
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1427  		/* reset the reference count (whiten the object) */
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1428  		object->count = 0;
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1429  		if (color_gray(object) && get_object(object))
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1430  			list_add_tail(&object->gray_list, &gray_list);
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1431  
8c96f1bc6fc49c He Zhe          2020-01-30  1432  		raw_spin_unlock_irqrestore(&object->lock, flags);
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1433  	}
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1434  	rcu_read_unlock();
3c7b4e6b8be4c1 Catalin Marinas 2009-06-11  1435  

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

Attachment: .config.gz
Description: application/gzip