Re: [RFC PATCH 4/6] tracing: wprobe: Add wprobe event trigger

Re: [RFC PATCH 4/6] tracing: wprobe: Add wprobe event trigger

[kernel test robot]

Hi Masami,

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

[auto build test WARNING on trace/for-next]
[also build test WARNING on tip/x86/core perf-tools-next/perf-tools-next tip/perf/core perf-tools/perf-tools peterz-queue/sched/core linus/master v6.17-rc4 next-20250902]
[cannot apply to acme/perf/core]
[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/Masami-Hiramatsu-Google/tracing-wprobe-Add-watchpoint-probe-event-based-on-hardware-breakpoint/20250901-225207
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/175673791934.478080.13510585438052558733.stgit%40devnote2
patch subject: [RFC PATCH 4/6] tracing: wprobe: Add wprobe event trigger
config: arm64-randconfig-001-20250902 (https://download.01.org/0day-ci/archive/20250902/202509021922.cDLHk0GU-lkp@intel.com/config)
compiler: aarch64-linux-gcc (GCC) 8.5.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250902/202509021922.cDLHk0GU-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/202509021922.cDLHk0GU-lkp@intel.com/

All warnings (new ones prefixed by >>):

   kernel/trace/trace_wprobe.c: In function '__trace_wprobe_create':
   kernel/trace/trace_wprobe.c:573:2: error: cleanup argument not a function
     const char *tplog __free(trace_probe_log_clear) = NULL;
     ^~~~~
   kernel/trace/trace_wprobe.c:585:8: error: void value not ignored as it ought to be
     tplog = trace_probe_log_init("wprobe", argc, argv);
           ^
   kernel/trace/trace_wprobe.c:573:14: warning: variable 'tplog' set but not used [-Wunused-but-set-variable]
     const char *tplog __free(trace_probe_log_clear) = NULL;
                 ^~~~~
   At top level:
>> kernel/trace/trace_wprobe.c:60:27: warning: 'trace_wprobe_local_perf' defined but not used [-Wunused-function]
    static struct perf_event *trace_wprobe_local_perf(struct trace_wprobe *tw)
                              ^~~~~~~~~~~~~~~~~~~~~~~


vim +/trace_wprobe_local_perf +60 kernel/trace/trace_wprobe.c

    58	
    59	/* This must be called under cpu locked (e.g. preempt off, irq off) */
  > 60	static struct perf_event *trace_wprobe_local_perf(struct trace_wprobe *tw)
    61	{
    62		return *this_cpu_ptr(tw->bp_event);
    63	}
    64	

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

Re: [RFC PATCH 4/6] tracing: wprobe: Add wprobe event trigger

[Masami Hiramatsu]

On Tue, 2 Sep 2025 19:34:30 +0800
kernel test robot <lkp@intel.com> wrote:

> Hi Masami,
> 
> [This is a private test report for your RFC patch.]
> kernel test robot noticed the following build warnings:
> 
> [auto build test WARNING on trace/for-next]
> [also build test WARNING on tip/x86/core perf-tools-next/perf-tools-next tip/perf/core perf-tools/perf-tools peterz-queue/sched/core linus/master v6.17-rc4 next-20250902]
> [cannot apply to acme/perf/core]
> [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/Masami-Hiramatsu-Google/tracing-wprobe-Add-watchpoint-probe-event-based-on-hardware-breakpoint/20250901-225207
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
> patch link:    https://lore.kernel.org/r/175673791934.478080.13510585438052558733.stgit%40devnote2
> patch subject: [RFC PATCH 4/6] tracing: wprobe: Add wprobe event trigger
> config: arm64-randconfig-001-20250902 (https://download.01.org/0day-ci/archive/20250902/202509021922.cDLHk0GU-lkp@intel.com/config)
> compiler: aarch64-linux-gcc (GCC) 8.5.0
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250902/202509021922.cDLHk0GU-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/202509021922.cDLHk0GU-lkp@intel.com/
> 
> All warnings (new ones prefixed by >>):
> 
>    kernel/trace/trace_wprobe.c: In function '__trace_wprobe_create':
>    kernel/trace/trace_wprobe.c:573:2: error: cleanup argument not a function
>      const char *tplog __free(trace_probe_log_clear) = NULL;
>      ^~~~~
>    kernel/trace/trace_wprobe.c:585:8: error: void value not ignored as it ought to be
>      tplog = trace_probe_log_init("wprobe", argc, argv);
>            ^
>    kernel/trace/trace_wprobe.c:573:14: warning: variable 'tplog' set but not used [-Wunused-but-set-variable]
>      const char *tplog __free(trace_probe_log_clear) = NULL;
>                  ^~~~~
>    At top level:
> >> kernel/trace/trace_wprobe.c:60:27: warning: 'trace_wprobe_local_perf' defined but not used [-Wunused-function]
>     static struct perf_event *trace_wprobe_local_perf(struct trace_wprobe *tw)
>                               ^~~~~~~~~~~~~~~~~~~~~~~

Indeed, CONFIG_WPROBE_TRIGGERS=n, it is not used. This is a real problem
in this version.

Thanks.

> 
> 
> vim +/trace_wprobe_local_perf +60 kernel/trace/trace_wprobe.c
> 
>     58	
>     59	/* This must be called under cpu locked (e.g. preempt off, irq off) */
>   > 60	static struct perf_event *trace_wprobe_local_perf(struct trace_wprobe *tw)
>     61	{
>     62		return *this_cpu_ptr(tw->bp_event);
>     63	}
>     64	
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki


-- 
Masami Hiramatsu (Google) <mhiramat@kernel.org>