Hi Sean, I love your patch! Perhaps something to improve: [auto build test WARNING on drm-intel/for-linux-next] [also build test WARNING on drm-exynos/exynos-drm-next tegra-drm/drm/tegra/for-next drm-tip/drm-tip linus/master v5.7 next-20200608] [cannot apply to drm/drm-next] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Sean-Paul/drm-trace-Mirror-DRM-debug-logs-to-tracefs/20200609-050750 base: git://anongit.freedesktop.org/drm-intel for-linux-next config: x86_64-randconfig-s021-20200607 (attached as .config) compiler: gcc-9 (Debian 9.3.0-13) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.1-247-gcadbd124-dirty # save the attached .config to linux build tree make W=1 C=1 ARCH=x86_64 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot sparse warnings: (new ones prefixed by >>) >> drivers/gpu/drm/drm_print.c:459:21: sparse: sparse: non-ANSI function declaration of function 'drm_trace_init' >> drivers/gpu/drm/drm_print.c:492:24: sparse: sparse: non-ANSI function declaration of function 'drm_trace_cleanup' Please review and possibly fold the followup patch. vim +/drm_trace_init +459 drivers/gpu/drm/drm_print.c 452 453 /** 454 * drm_trace_init - initializes the drm trace array 455 * 456 * This function fetches (or creates) the drm trace array. This should be called 457 * once on drm subsystem creation and matched with drm_trace_cleanup(). 458 */ > 459 void drm_trace_init() 460 { 461 trace_arr = trace_array_get_by_name("drm"); 462 if (!trace_arr) 463 return; 464 } 465 EXPORT_SYMBOL(drm_trace_init); 466 467 /** 468 * drm_trace_printf - adds an entry to the drm tracefs instance 469 * @format: printf format of the message to add to the trace 470 * 471 * This function adds a new entry in the drm tracefs instance 472 */ 473 void drm_trace_printf(const char *format, ...) 474 { 475 struct va_format vaf; 476 va_list args; 477 478 va_start(args, format); 479 vaf.fmt = format; 480 vaf.va = &args; 481 trace_array_printk(trace_arr, _THIS_IP_, "%pV", &vaf); 482 va_end(args); 483 } 484 485 /** 486 * drm_trace_cleanup - destroys the drm trace array 487 * 488 * This function destroys the drm trace array created with drm_trace_init. This 489 * should be called once on drm subsystem close and matched with 490 * drm_trace_init(). 491 */ > 492 void drm_trace_cleanup() --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org