Hi "Marek, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on net-next/master] url: https://github.com/0day-ci/linux/commits/Marek-Beh-n/Add-support-for-LEDs... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git 59632b220f2d61df274ed3a14a204e941051fdad config: powerpc-randconfig-r005-20200716 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ed6b578040a85977026c93bf4188f996148f3218) reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # install powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): if (sysfs_streq(buf, "none")) { ^~~~~~~~~~~~~~~~~~~~~~~~ drivers/leds/led-triggers.c:74:9: note: uninitialized use occurs here return ret < 0 ? ret : count; ^~~ drivers/leds/led-triggers.c:52:2: note: remove the 'if' if its condition is always false if (sysfs_streq(buf, "none")) { ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ drivers/leds/led-triggers.c:43:9: note: initialize the variable 'ret' to silence this warning int ret; ^ = 0 1 warning generated. vim +52 drivers/leds/led-triggers.c abf0e9916c9400 Marek Behún 2020-07-16 35 11f70002213774 Akinobu Mita 2019-09-29 36 ssize_t led_trigger_write(struct file *filp, struct kobject *kobj, 11f70002213774 Akinobu Mita 2019-09-29 37 struct bin_attribute *bin_attr, char *buf, 11f70002213774 Akinobu Mita 2019-09-29 38 loff_t pos, size_t count) c3bc9956ec52fb Richard Purdie 2006-03-31 39 { 11f70002213774 Akinobu Mita 2019-09-29 40 struct device *dev = kobj_to_dev(kobj); f8a7c6fe14f556 Richard Purdie 2007-07-08 41 struct led_classdev *led_cdev = dev_get_drvdata(dev); c3bc9956ec52fb Richard Purdie 2006-03-31 42 struct led_trigger *trig; 979669942e8602 Marek Behún 2020-07-16 43 int ret; acd899e4f3066b Jacek Anaszewski 2014-09-22 44 acd899e4f3066b Jacek Anaszewski 2014-09-22 45 mutex_lock(&led_cdev->led_access); acd899e4f3066b Jacek Anaszewski 2014-09-22 46 acd899e4f3066b Jacek Anaszewski 2014-09-22 47 if (led_sysfs_is_disabled(led_cdev)) { acd899e4f3066b Jacek Anaszewski 2014-09-22 48 ret = -EBUSY; acd899e4f3066b Jacek Anaszewski 2014-09-22 49 goto unlock; acd899e4f3066b Jacek Anaszewski 2014-09-22 50 } c3bc9956ec52fb Richard Purdie 2006-03-31 51 7296c33ed12ef1 Heiner Kallweit 2016-03-08 @52 if (sysfs_streq(buf, "none")) { 0013b23d66a276 Németh Márton 2008-03-09 53 led_trigger_remove(led_cdev); acd899e4f3066b Jacek Anaszewski 2014-09-22 54 goto unlock; c3bc9956ec52fb Richard Purdie 2006-03-31 55 } c3bc9956ec52fb Richard Purdie 2006-03-31 56 dc47206e552c08 Richard Purdie 2007-11-10 57 down_read(&triggers_list_lock); c3bc9956ec52fb Richard Purdie 2006-03-31 58 list_for_each_entry(trig, &trigger_list, next_trig) { abf0e9916c9400 Marek Behún 2020-07-16 59 if (sysfs_streq(buf, trig->name) && trigger_relevant(led_cdev, trig)) { dc47206e552c08 Richard Purdie 2007-11-10 60 down_write(&led_cdev->trigger_lock); 979669942e8602 Marek Behún 2020-07-16 61 ret = led_trigger_set(led_cdev, trig); dc47206e552c08 Richard Purdie 2007-11-10 62 up_write(&led_cdev->trigger_lock); c3bc9956ec52fb Richard Purdie 2006-03-31 63 dc47206e552c08 Richard Purdie 2007-11-10 64 up_read(&triggers_list_lock); acd899e4f3066b Jacek Anaszewski 2014-09-22 65 goto unlock; c3bc9956ec52fb Richard Purdie 2006-03-31 66 } c3bc9956ec52fb Richard Purdie 2006-03-31 67 } a3eac76cdf7225 Heiner Kallweit 2016-07-01 68 /* we come here only if buf matches no trigger */ a3eac76cdf7225 Heiner Kallweit 2016-07-01 69 ret = -EINVAL; dc47206e552c08 Richard Purdie 2007-11-10 70 up_read(&triggers_list_lock); c3bc9956ec52fb Richard Purdie 2006-03-31 71 acd899e4f3066b Jacek Anaszewski 2014-09-22 72 unlock: acd899e4f3066b Jacek Anaszewski 2014-09-22 73 mutex_unlock(&led_cdev->led_access); 979669942e8602 Marek Behún 2020-07-16 74 return ret < 0 ? ret : count; c3bc9956ec52fb Richard Purdie 2006-03-31 75 } 11f70002213774 Akinobu Mita 2019-09-29 76 EXPORT_SYMBOL_GPL(led_trigger_write); c3bc9956ec52fb Richard Purdie 2006-03-31 77 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org