Re: [tip: timers/core] posix-cpu-timers: Use common permission check in posix_cpu_clock_get()

[kbuild test robot]

Hi tip-bot2,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[cannot apply to v5.3-rc6 next-20190827]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/tip-bot2-for-Thomas-Gleixner/posix-cpu-timers-Use-common-permission-check-in-posix_cpu_clock_get/20190829-181227
config: nds32-defconfig (attached as .config)
compiler: nds32le-linux-gcc (GCC) 8.1.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        GCC_VERSION=8.1.0 make.cross ARCH=nds32 

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

All warnings (new ones prefixed by >>):

   kernel/time/posix-cpu-timers.c: In function 'posix_cpu_clock_get':
   kernel/time/posix-cpu-timers.c:275:8: error: implicit declaration of function 'get_task_for_clock'; did you mean 'get_task_struct'? [-Werror=implicit-function-declaration]
     tsk = get_task_for_clock(clock);
           ^~~~~~~~~~~~~~~~~~
           get_task_struct
>> kernel/time/posix-cpu-timers.c:275:6: warning: assignment to 'struct task_struct *' from 'int' makes pointer from integer without a cast [-Wint-conversion]
     tsk = get_task_for_clock(clock);
         ^
   cc1: some warnings being treated as errors

vim +275 kernel/time/posix-cpu-timers.c

   268	
   269	static int posix_cpu_clock_get(const clockid_t clock, struct timespec64 *tp)
   270	{
   271		const clockid_t clkid = CPUCLOCK_WHICH(clock);
   272		struct task_struct *tsk;
   273		u64 t;
   274	
 > 275		tsk = get_task_for_clock(clock);
   276		if (!tsk)
   277			return -EINVAL;
   278	
   279		if (CPUCLOCK_PERTHREAD(clock))
   280			cpu_clock_sample(clkid, tsk, &t);
   281		else
   282			cpu_clock_sample_group(clkid, tsk, &t);
   283		put_task_struct(tsk);
   284	
   285		*tp = ns_to_timespec64(t);
   286		return 0;
   287	}
   288	

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0-DAY kernel test infrastructure                Open Source Technology Center
https://lists.01.org/pipermail/kbuild-all                   Intel Corporation

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