Re: [PATCH 6/6] drm: zynqmp_dp: Add debugfs interface for compliance testing

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

Hi Sean,

kernel test robot noticed the following build warnings:

[auto build test WARNING on v6.8]
[cannot apply to drm-misc/drm-misc-next linus/master next-20240315]
[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/Sean-Anderson/drm-zynqmp_dp-Downgrade-log-level-for-aux-retries-message/20240316-071208
base:   v6.8
patch link:    https://lore.kernel.org/r/20240315230916.1759060-7-sean.anderson%40linux.dev
patch subject: [PATCH 6/6] drm: zynqmp_dp: Add debugfs interface for compliance testing
config: microblaze-allmodconfig (https://download.01.org/0day-ci/archive/20240316/202403161704.ACHJdSJG-lkp@intel.com/config)
compiler: microblaze-linux-gcc (GCC) 13.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240316/202403161704.ACHJdSJG-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/202403161704.ACHJdSJG-lkp@intel.com/

All warnings (new ones prefixed by >>):

   drivers/gpu/drm/xlnx/zynqmp_dp.c: In function 'zynqmp_dp_bridge_debugfs_init':
>> drivers/gpu/drm/xlnx/zynqmp_dp.c:2168:31: warning: 'sprintf' may write a terminating nul past the end of the destination [-Wformat-overflow=]
    2168 |                 sprintf(name, fmt, i);
         |                               ^~~
   drivers/gpu/drm/xlnx/zynqmp_dp.c:2168:17: note: 'sprintf' output between 18 and 20 bytes into a destination of size 19
    2168 |                 sprintf(name, fmt, i);
         |                 ^~~~~~~~~~~~~~~~~~~~~


vim +/sprintf +2168 drivers/gpu/drm/xlnx/zynqmp_dp.c

  2136	
  2137	DEFINE_DEBUGFS_ATTRIBUTE(fops_zynqmp_dp_rate, zynqmp_dp_rate_get,
  2138				 zynqmp_dp_rate_set, "%llu\n");
  2139	
  2140	static void zynqmp_dp_bridge_debugfs_init(struct drm_bridge *bridge,
  2141						  struct dentry *root)
  2142	{
  2143		struct zynqmp_dp *dp = bridge_to_dp(bridge);
  2144		struct dentry *test;
  2145		int i;
  2146	
  2147		dp->test.bw_code = DP_LINK_BW_5_4;
  2148		dp->test.link_cnt = dp->num_lanes;
  2149	
  2150		test = debugfs_create_dir("test", root);
  2151	#define CREATE_FILE(name) \
  2152		debugfs_create_file(#name, 0600, test, dp, &fops_zynqmp_dp_##name)
  2153		CREATE_FILE(pattern);
  2154		CREATE_FILE(enhanced);
  2155		CREATE_FILE(downspread);
  2156		CREATE_FILE(active);
  2157		CREATE_FILE(custom);
  2158		CREATE_FILE(rate);
  2159		CREATE_FILE(lanes);
  2160	
  2161		for (i = 0; i < dp->num_lanes; i++) {
  2162			static const char fmt[] = "lane%d_preemphasis";
  2163			char name[sizeof(fmt)];
  2164	
  2165			dp->debugfs_train_set[i].dp = dp;
  2166			dp->debugfs_train_set[i].lane = i;
  2167	
> 2168			sprintf(name, fmt, i);
  2169			debugfs_create_file(name, 0600, test,
  2170					    &dp->debugfs_train_set[i],
  2171					    &fops_zynqmp_dp_preemphasis);
  2172	
  2173			sprintf(name, "lane%d_swing", i);
  2174			debugfs_create_file(name, 0600, test,
  2175					    &dp->debugfs_train_set[i],
  2176					    &fops_zynqmp_dp_swing);
  2177		}
  2178	}
  2179	

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