Re: [PATCH 7/7] tracing: Add syscall_user_buf_size to limit amount written

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

Hi Steven,

kernel test robot noticed the following build errors:

[auto build test ERROR on trace/for-next]
[also build test ERROR on linus/master v6.16 next-20250806]
[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/Steven-Rostedt/tracing-Replace-syscall-RCU-pointer-assignment-with-READ-WRITE_ONCE/20250806-122312
base:   https://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace for-next
patch link:    https://lore.kernel.org/r/20250805193235.747004484%40kernel.org
patch subject: [PATCH 7/7] tracing: Add syscall_user_buf_size to limit amount written
config: hexagon-randconfig-002-20250806 (https://download.01.org/0day-ci/archive/20250806/202508062211.cwYqtLu0-lkp@intel.com/config)
compiler: clang version 22.0.0git (https://github.com/llvm/llvm-project 7b8dea265e72c3037b6b1e54d5ab51b7e14f328b)
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250806/202508062211.cwYqtLu0-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/202508062211.cwYqtLu0-lkp@intel.com/

All errors (new ones prefixed by >>):

>> kernel/trace/trace.c:11128:32: error: use of undeclared identifier 'CONFIG_TRACE_SYSCALL_BUF_SIZE_DEFAULT'
    11128 |         global_trace.syscall_buf_sz = CONFIG_TRACE_SYSCALL_BUF_SIZE_DEFAULT;
          |                                       ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   1 error generated.


vim +/CONFIG_TRACE_SYSCALL_BUF_SIZE_DEFAULT +11128 kernel/trace/trace.c

 11110	
 11111		init_trace_flags_index(&global_trace);
 11112	
 11113		register_tracer(&nop_trace);
 11114	
 11115		/* Function tracing may start here (via kernel command line) */
 11116		init_function_trace();
 11117	
 11118		/* All seems OK, enable tracing */
 11119		tracing_disabled = 0;
 11120	
 11121		atomic_notifier_chain_register(&panic_notifier_list,
 11122					       &trace_panic_notifier);
 11123	
 11124		register_die_notifier(&trace_die_notifier);
 11125	
 11126		global_trace.flags = TRACE_ARRAY_FL_GLOBAL;
 11127	
 11128		global_trace.syscall_buf_sz = CONFIG_TRACE_SYSCALL_BUF_SIZE_DEFAULT;
 11129	
 11130		INIT_LIST_HEAD(&global_trace.systems);
 11131		INIT_LIST_HEAD(&global_trace.events);
 11132		INIT_LIST_HEAD(&global_trace.hist_vars);
 11133		INIT_LIST_HEAD(&global_trace.err_log);
 11134		list_add(&global_trace.marker_list, &marker_copies);
 11135		list_add(&global_trace.list, &ftrace_trace_arrays);
 11136	
 11137		apply_trace_boot_options();
 11138	
 11139		register_snapshot_cmd();
 11140	
 11141		return 0;
 11142	
 11143	out_free_pipe_cpumask:
 11144		free_cpumask_var(global_trace.pipe_cpumask);
 11145	out_free_savedcmd:
 11146		trace_free_saved_cmdlines_buffer();
 11147	out_free_temp_buffer:
 11148		ring_buffer_free(temp_buffer);
 11149	out_rm_hp_state:
 11150		cpuhp_remove_multi_state(CPUHP_TRACE_RB_PREPARE);
 11151	out_free_cpumask:
 11152		free_cpumask_var(global_trace.tracing_cpumask);
 11153	out_free_buffer_mask:
 11154		free_cpumask_var(tracing_buffer_mask);
 11155		return ret;
 11156	}
 11157	

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