Re: [PATCH] watchdog/mm: Allow dumping memory info in pretimeout

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

Hi Vincent,

kernel test robot noticed the following build warnings:

[auto build test WARNING on 9561de3a55bed6bdd44a12820ba81ec416e705a7]

url:    https://github.com/intel-lab-lkp/linux/commits/Vincent-Whitchurch/watchdog-mm-Allow-dumping-memory-info-in-pretimeout/20230609-144807
base:   9561de3a55bed6bdd44a12820ba81ec416e705a7
patch link:    https://lore.kernel.org/r/20230608-pretimeout-oom-v1-1-542cc91062d7%40axis.com
patch subject: [PATCH] watchdog/mm: Allow dumping memory info in pretimeout
config: parisc-buildonly-randconfig-r006-20230608 (https://download.01.org/0day-ci/archive/20230609/202306091651.GsOxG35Q-lkp@intel.com/config)
compiler: hppa-linux-gcc (GCC) 12.3.0
reproduce (this is a W=1 build):
        mkdir -p ~/bin
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        git checkout 9561de3a55bed6bdd44a12820ba81ec416e705a7
        b4 shazam https://lore.kernel.org/r/20230608-pretimeout-oom-v1-1-542cc91062d7@axis.com
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.3.0 ~/bin/make.cross W=1 O=build_dir ARCH=parisc olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.3.0 ~/bin/make.cross W=1 O=build_dir ARCH=parisc SHELL=/bin/bash

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/202306091651.GsOxG35Q-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> mm/oom_kill.c:156:21: warning: no previous prototype for 'find_trylock_task_mm' [-Wmissing-prototypes]
     156 | struct task_struct *find_trylock_task_mm(struct task_struct *p)
         |                     ^~~~~~~~~~~~~~~~~~~~


vim +/find_trylock_task_mm +156 mm/oom_kill.c

   151	
   152	/*
   153	 * Identical to the above, except that we avoid tasks which we can't lock, to
   154	 * avoid deadlocks when called from an interrupt handler.
   155	 */
 > 156	struct task_struct *find_trylock_task_mm(struct task_struct *p)
   157	{
   158		struct task_struct *t;
   159	
   160		rcu_read_lock();
   161	
   162		for_each_thread(p, t) {
   163			if (!task_trylock(t))
   164				continue;
   165			if (likely(t->mm))
   166				goto found;
   167			task_unlock(t);
   168		}
   169		t = NULL;
   170	found:
   171		rcu_read_unlock();
   172	
   173		return t;
   174	}
   175	

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