[jsarha:topic/chromeos-4.19-s0ix 6418/9999] kernel/time/posix-timers.c:1071:5: warning: no previous prototype for function 'ksys_clock_adjtime'

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

Hi Masahiro,

First bad commit (maybe != root cause):

tree:   https://github.com/jsarha/linux topic/chromeos-4.19-s0ix
head:   430bdaa0a8c38697780f45a148964d71951df11f
commit: 4fae0a1dc645742f2ecd6238813b2d30d4fb31cd [6418/9999] UPSTREAM: kbuild: add some extra warning flags unconditionally
config: mips-omega2p_defconfig (https://download.01.org/0day-ci/archive/20230606/202306061203.eboGlnYd-lkp@intel.com/config)
compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a)
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
        # install mips cross compiling tool for clang build
        # apt-get install binutils-mipsel-linux-gnu
        # https://github.com/jsarha/linux/commit/4fae0a1dc645742f2ecd6238813b2d30d4fb31cd
        git remote add jsarha https://github.com/jsarha/linux
        git fetch --no-tags jsarha topic/chromeos-4.19-s0ix
        git checkout 4fae0a1dc645742f2ecd6238813b2d30d4fb31cd
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=mips olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=mips SHELL=/bin/bash M=kernel/time

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202306061203.eboGlnYd-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from kernel/time/posix-timers.c:47:
   In file included from include/linux/syscalls.h:85:
   In file included from include/trace/syscall.h:7:
   In file included from include/linux/trace_events.h:7:
   In file included from include/linux/trace_seq.h:5:
   include/linux/seq_buf.h:35:12: warning: assigning to 'char *' from 'unsigned char *' converts between pointers to integer types where one is of the unique plain 'char' type and the other is not [-Wpointer-sign]
      35 |         s->buffer = buf;
         |                   ^ ~~~
   In file included from kernel/time/posix-timers.c:47:
   In file included from include/linux/syscalls.h:85:
   In file included from include/trace/syscall.h:7:
   In file included from include/linux/trace_events.h:10:
   In file included from include/linux/perf_event.h:57:
   In file included from include/linux/cgroup.h:28:
   include/linux/cgroup-defs.h:469:16: warning: field 'cgrp' with variable sized type 'struct cgroup' not at the end of a struct or class is a GNU extension [-Wgnu-variable-sized-type-not-at-end]
     469 |         struct cgroup cgrp;
         |                       ^
>> kernel/time/posix-timers.c:1071:5: warning: no previous prototype for function 'ksys_clock_adjtime' [-Wmissing-prototypes]
    1071 | int ksys_clock_adjtime(const clockid_t which_clock, struct timex __user * utx)
         |     ^
   kernel/time/posix-timers.c:1071:1: note: declare 'static' if the function is not intended to be used outside of this translation unit
    1071 | int ksys_clock_adjtime(const clockid_t which_clock, struct timex __user * utx)
         | ^
         | static 
   3 warnings generated.
   Assembler messages:
   Fatal error: invalid -march= option: `mips32r2'
   clang: error: assembler command failed with exit code 1 (use -v to see invocation)


vim +/ksys_clock_adjtime +1071 kernel/time/posix-timers.c

^1da177e4c3f41 kernel/posix-timers.c      Linus Torvalds    2005-04-16  1070  
c2185294ad509e kernel/time/posix-timers.c Guenter Roeck     2018-09-21 @1071  int ksys_clock_adjtime(const clockid_t which_clock, struct timex __user * utx)
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1072  {
d3ba5a9a345b12 kernel/time/posix-timers.c Christoph Hellwig 2017-05-26  1073  	const struct k_clock *kc = clockid_to_kclock(which_clock);
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1074  	struct timex ktx;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1075  	int err;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1076  
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1077  	if (!kc)
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1078  		return -EINVAL;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1079  	if (!kc->clock_adj)
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1080  		return -EOPNOTSUPP;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1081  
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1082  	if (copy_from_user(&ktx, utx, sizeof(ktx)))
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1083  		return -EFAULT;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1084  
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1085  	err = kc->clock_adj(which_clock, &ktx);
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1086  
f0dbe81f0e7c39 kernel/posix-timers.c      Miroslav Lichvar  2013-01-11  1087  	if (err >= 0 && copy_to_user(utx, &ktx, sizeof(ktx)))
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1088  		return -EFAULT;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1089  
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1090  	return err;
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1091  }
f1f1d5ebd10ffa kernel/posix-timers.c      Richard Cochran   2011-02-01  1092  

:::::: The code at line 1071 was first introduced by commit
:::::: c2185294ad509ea4a6859dc0b4c5e21a9f4ee224 CHROMIUM: alt-syscall: Make required syscalls available for use

:::::: TO: Guenter Roeck <groeck@chromium.org>
:::::: CC: Guenter Roeck <groeck@chromium.org>

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