Re: [RFC PATCH v1 6/9] freezer: Set default freeze priority for zombie tasks

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

Hi Zihuan,

[This is a private test report for your RFC patch.]
kernel test robot noticed the following build errors:

[auto build test ERROR on akpm-mm/mm-everything]
[also build test ERROR on brauner-vfs/vfs.all linus/master v6.16 next-20250807]
[cannot apply to tip/sched/core kees/for-next/execve]
[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/Zihuan-Zhang/freezer-Introduce-freeze_priority-field-in-task_struct/20250807-201611
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/20250807121418.139765-7-zhangzihuan%40kylinos.cn
patch subject: [RFC PATCH v1 6/9] freezer: Set default freeze priority for zombie tasks
config: arm-randconfig-002-20250808 (https://download.01.org/0day-ci/archive/20250808/202508080845.gESj6omH-lkp@intel.com/config)
compiler: arm-linux-gnueabi-gcc (GCC) 10.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250808/202508080845.gESj6omH-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/202508080845.gESj6omH-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from kernel/sched/core.c:45:
   include/linux/freezer.h: In function 'freeze_set_default_priority':
   include/linux/freezer.h:95:55: warning: no return statement in function returning non-void [-Wreturn-type]
      95 | static inline bool freeze_set_default_priority(struct task_struct *p, unsigned int prio) {}
         |                                                       ^~~~~~~~~~~
   kernel/sched/core.c: In function 'do_task_dead':
>> kernel/sched/core.c:6984:39: error: 'FREEZE_PRIORITY_NEVER' undeclared (first use in this function)
    6984 |  freeze_set_default_priority(current, FREEZE_PRIORITY_NEVER);
         |                                       ^~~~~~~~~~~~~~~~~~~~~
   kernel/sched/core.c:6984:39: note: each undeclared identifier is reported only once for each function it appears in


vim +/FREEZE_PRIORITY_NEVER +6984 kernel/sched/core.c

  6974	
  6975	void __noreturn do_task_dead(void)
  6976	{
  6977		/* Causes final put_task_struct in finish_task_switch(): */
  6978		set_special_state(TASK_DEAD);
  6979	
  6980		/* Tell freezer to ignore us: */
  6981		current->flags |= PF_NOFREEZE;
  6982	
  6983		__schedule(SM_NONE);
> 6984		freeze_set_default_priority(current, FREEZE_PRIORITY_NEVER);
  6985		BUG();
  6986	
  6987		/* Avoid "noreturn function does return" - but don't continue if BUG() is a NOP: */
  6988		for (;;)
  6989			cpu_relax();
  6990	}
  6991	

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