Re: [PATCH] tracing/hist: make err_text array fully const

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

Hi Huiwen,

kernel test robot noticed the following build warnings:

[auto build test WARNING on trace/for-next]
[also build test WARNING on linus/master v6.18-rc4 next-20251104]
[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/Huiwen-He/tracing-hist-make-err_text-array-fully-const/20251104-125932
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20251104045558.1644671-1-hehuiwen%40kylinos.cn
patch subject: [PATCH] tracing/hist: make err_text array fully const
config: riscv-randconfig-001-20251105 (https://download.01.org/0day-ci/archive/20251105/202511051436.6ZUGn3Af-lkp@intel.com/config)
compiler: riscv32-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251105/202511051436.6ZUGn3Af-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/202511051436.6ZUGn3Af-lkp@intel.com/

All warnings (new ones prefixed by >>):

   kernel/trace/trace_events_hist.c: In function 'hist_err':
>> kernel/trace/trace_events_hist.c:808:46: warning: passing argument 4 of 'tracing_log_err' discards 'const' qualifier from pointer target type [-Wdiscarded-qualifiers]
     tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
                                                 ^~~~~~~~
   In file included from kernel/trace/trace_dynevent.h:14,
                    from kernel/trace/trace_synth.h:5,
                    from kernel/trace/trace_events_hist.c:22:
   kernel/trace/trace.h:2113:21: note: expected 'const char **' but argument is of type 'const char * const*'
           const char **errs, u8 type, u16 pos);
           ~~~~~~~~~~~~~^~~~


vim +808 kernel/trace/trace_events_hist.c

4b147936fa50965 Tom Zanussi      2018-01-15  802  
edfeed318d59ff2 Tom Zanussi      2022-01-28  803  static void hist_err(struct trace_array *tr, u8 err_type, u16 err_pos)
7bbab38d07f3185 Masami Hiramatsu 2018-11-05  804  {
edfeed318d59ff2 Tom Zanussi      2022-01-28  805  	if (!last_cmd)
edfeed318d59ff2 Tom Zanussi      2022-01-28  806  		return;
edfeed318d59ff2 Tom Zanussi      2022-01-28  807  
726721a51838e39 Tom Zanussi      2020-05-28 @808  	tracing_log_err(tr, last_cmd_loc, last_cmd, err_text,
726721a51838e39 Tom Zanussi      2020-05-28  809  			err_type, err_pos);
7bbab38d07f3185 Masami Hiramatsu 2018-11-05  810  }
7bbab38d07f3185 Masami Hiramatsu 2018-11-05  811  

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