Hi Souradeep, kernel test robot noticed the following build warnings: [auto build test WARNING on char-misc/char-misc-testing] [also build test WARNING on char-misc/char-misc-next char-misc/char-misc-linus linus/master v6.3-rc7 next-20230417] [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/Souradeep-Chowdhury/dt-bindings-misc-qcom-dcc-Add-the-dtschema/20230414-220304 patch link: https://lore.kernel.org/r/b1a9cbbcfefe133cc9047a71a2acdaa74239df29.1681480351.git.quic_schowdhu%40quicinc.com patch subject: [PATCH V1 2/3] drivers: misc: dcc: Add driver support for Data Capture and Compare unit(DCC) config: arm64-allmodconfig (https://download.01.org/0day-ci/archive/20230418/202304181327.0grVYsHS-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 9638da200e00bd069e6dd63604e14cbafede9324) 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 arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/f3f73f6008e1ebca6fba848e260b1f938d91be95 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Souradeep-Chowdhury/dt-bindings-misc-qcom-dcc-Add-the-dtschema/20230414-220304 git checkout f3f73f6008e1ebca6fba848e260b1f938d91be95 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm64 SHELL=/bin/bash drivers/misc/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Link: https://lore.kernel.org/oe-kbuild-all/202304181327.0grVYsHS-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): >> drivers/misc/dcc.c:217:14: warning: variable 'ret' is used uninitialized whenever 'for' loop exits because its condition is false [-Wsometimes-uninitialized] for (i = 0; i < drvdata->nr_link_list; i++) { ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/misc/dcc.c:238:9: note: uninitialized use occurs here return ret; ^~~ drivers/misc/dcc.c:217:14: note: remove the condition if it is always true for (i = 0; i < drvdata->nr_link_list; i++) { ^~~~~~~~~~~~~~~~~~~~~~~~~ drivers/misc/dcc.c:190:9: note: initialize the variable 'ret' to silence this warning int ret; ^ = 0 1 warning generated. vim +217 drivers/misc/dcc.c 186 187 static int dcc_sw_trigger(struct dcc_drvdata *drvdata) 188 { 189 void __iomem *addr; 190 int ret; 191 int i; 192 u32 status; 193 u32 ll_cfg; 194 u32 tmp_ll_cfg; 195 u32 val; 196 197 mutex_lock(&drvdata->mutex); 198 199 for (i = 0; i < drvdata->nr_link_list; i++) { 200 if (!test_bit(i, drvdata->enable_bitmap)) 201 continue; 202 ll_cfg = dcc_list_readl(drvdata, i, DCC_LL_CFG); 203 tmp_ll_cfg = ll_cfg & ~DCC_TRIGGER_MASK; 204 dcc_list_writel(drvdata, tmp_ll_cfg, i, DCC_LL_CFG); 205 dcc_list_writel(drvdata, 1, i, DCC_LL_SW_TRIGGER); 206 dcc_list_writel(drvdata, ll_cfg, i, DCC_LL_CFG); 207 } 208 209 addr = drvdata->base + DCC_STATUS(drvdata->mem_map_ver); 210 if (readl_poll_timeout(addr, val, !FIELD_GET(DCC_STATUS_MASK, val), 211 1, STATUS_READY_TIMEOUT)) { 212 dev_err(drvdata->dev, "DCC is busy after receiving sw trigger\n"); 213 ret = -EBUSY; 214 goto out_unlock; 215 } 216 > 217 for (i = 0; i < drvdata->nr_link_list; i++) { 218 if (!test_bit(i, drvdata->enable_bitmap)) 219 continue; 220 221 status = dcc_list_readl(drvdata, i, DCC_LL_BUS_ACCESS_STATUS); 222 if (!status) 223 continue; 224 225 dev_err(drvdata->dev, "Read access error for list %d err: 0x%x\n", 226 i, status); 227 ll_cfg = dcc_list_readl(drvdata, i, DCC_LL_CFG); 228 tmp_ll_cfg = ll_cfg & ~DCC_TRIGGER_MASK; 229 dcc_list_writel(drvdata, tmp_ll_cfg, i, DCC_LL_CFG); 230 dcc_list_writel(drvdata, DCC_STATUS_MASK, i, DCC_LL_BUS_ACCESS_STATUS); 231 dcc_list_writel(drvdata, ll_cfg, i, DCC_LL_CFG); 232 ret = -ENODATA; 233 break; 234 } 235 236 out_unlock: 237 mutex_unlock(&drvdata->mutex); 238 return ret; 239 } 240 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests