tree: https://github.com/frank-w/BPI-R2-4.14 5.11-rc head: 53902a2a421d0384bda73803e4df56ff3fbc1bc6 commit: c73dac68fd0eb1d172e2c05813e37f5830f18672 [15/18] mt6625l: include wifi-code config: arm-allyesconfig (attached as .config) compiler: arm-linux-gnueabi-gcc (GCC) 9.3.0 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 # https://github.com/frank-w/BPI-R2-4.14/commit/c73dac68fd0eb1d172e2c05813e... git remote add frank-w-bpi-r2-4.14 https://github.com/frank-w/BPI-R2-4.14 git fetch --no-tags frank-w-bpi-r2-4.14 5.11-rc git checkout c73dac68fd0eb1d172e2c05813e37f5830f18672 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm 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 >>): In file included from drivers/misc/mediatek/btif/common/plat_inc/btif_pub.h:17, from drivers/misc/mediatek/btif/common/mtk_btif.c:37: drivers/misc/mediatek/btif/common/plat_inc/plat_common.h: In function 'hal_log_print': 64 | vsnprintf(temp_sring, DBG_LOG_STR_SIZE, str, args); | ^~~~~~~~~ drivers/misc/mediatek/btif/common/mtk_btif.c: In function 'mtk_btif_restore_noirq': 379 | int i_ret = 0; | ^~~~~ drivers/misc/mediatek/btif/common/mtk_btif.c: In function 'flag_store': 773 | int result = 0; | ^~~~~~ drivers/misc/mediatek/btif/common/mtk_btif.c: In function 'btif_log_buf_dmp_out': 3029 | unsigned char *p_buf = NULL; | ^~~~~ -- In file included from drivers/misc/mediatek/btif/common/plat_inc/btif_pub.h:17, from drivers/misc/mediatek/btif/common/inc/mtk_btif.h:37, from drivers/misc/mediatek/btif/common/mtk_btif_exp.c:20: drivers/misc/mediatek/btif/common/plat_inc/plat_common.h: In function 'hal_log_print': 64 | vsnprintf(temp_sring, DBG_LOG_STR_SIZE, str, args); | ^~~~~~~~~ -- In file included from drivers/misc/mediatek/btif/common/plat_inc/btif_dma_pub.h:19, from drivers/misc/mediatek/btif/common/plat_inc/btif_dma_priv.h:18, from drivers/misc/mediatek/btif/common/btif_dma_plat.c:22: drivers/misc/mediatek/btif/common/plat_inc/plat_common.h: In function 'hal_log_print': 64 | vsnprintf(temp_sring, DBG_LOG_STR_SIZE, str, args); | ^~~~~~~~~ drivers/misc/mediatek/btif/common/btif_dma_plat.c: In function 'hal_dma_pm_ops': 1313 | unsigned int flag = 0; | ^~~~ -- In file included from drivers/misc/mediatek/btif/common/plat_inc/btif_pub.h:17, from drivers/misc/mediatek/btif/common/btif_plat.c:21: drivers/misc/mediatek/btif/common/plat_inc/plat_common.h: In function 'hal_log_print': 64 | vsnprintf(temp_sring, DBG_LOG_STR_SIZE, str, args); | ^~~~~~~~~ drivers/misc/mediatek/btif/common/btif_plat.c: In function 'hal_btif_pm_ops': 1343 | unsigned int flag = 0; | ^~~~ vim +64 drivers/misc/mediatek/btif/common/plat_inc/plat_common.h b9e0bfd476882d Frank Wunderlich 2020-12-28 56 b9e0bfd476882d Frank Wunderlich 2020-12-28 57 /*Log defination*/ b9e0bfd476882d Frank Wunderlich 2020-12-28 58 static int hal_log_print(const char *str, ...) b9e0bfd476882d Frank Wunderlich 2020-12-28 59 { b9e0bfd476882d Frank Wunderlich 2020-12-28 60 va_list args; b9e0bfd476882d Frank Wunderlich 2020-12-28 61 char temp_sring[DBG_LOG_STR_SIZE]; b9e0bfd476882d Frank Wunderlich 2020-12-28 62 b9e0bfd476882d Frank Wunderlich 2020-12-28 63 va_start(args, str); b9e0bfd476882d Frank Wunderlich 2020-12-28 @64 vsnprintf(temp_sring, DBG_LOG_STR_SIZE, str, args); b9e0bfd476882d Frank Wunderlich 2020-12-28 65 va_end(args); b9e0bfd476882d Frank Wunderlich 2020-12-28 66 b9e0bfd476882d Frank Wunderlich 2020-12-28 67 pr_err("%s", temp_sring); b9e0bfd476882d Frank Wunderlich 2020-12-28 68 b9e0bfd476882d Frank Wunderlich 2020-12-28 69 return 0; b9e0bfd476882d Frank Wunderlich 2020-12-28 70 } b9e0bfd476882d Frank Wunderlich 2020-12-28 71 :::::: The code at line 64 was first introduced by commit :::::: b9e0bfd476882d78671888c3102843cce617edbd mt6625l: add driver from 5.10 :::::: TO: Frank Wunderlich <frank-w(a)public-files.de&gt; :::::: CC: Frank Wunderlich <frank-w(a)public-files.de&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org