tree: https://chromium.googlesource.com/chromiumos/third_party/kernel chromeos-4.19 head: d7fbffc4196415cc9fa9db9d797234cd6ccedab0 commit: d7fbffc4196415cc9fa9db9d797234cd6ccedab0 [4/4] CHROMIUM: drm/mediatek: add display debug patch config: arm64-chromiumos-arm64-customedconfig-chrome-os:chromeos-4.19:a50b3b83f7144bbdd92fc8889fbdc177f1fb09a9 (attached as .config) compiler: aarch64-linux-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 git remote add chrome-os https://chromium.googlesource.com/chromiumos/third_party/kernel git fetch --no-tags chrome-os chromeos-4.19 git checkout d7fbffc4196415cc9fa9db9d797234cd6ccedab0 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from include/linux/printk.h:7, from include/linux/kernel.h:14, from include/linux/list.h:9, from include/linux/agp_backend.h:33, from include/drm/drmP.h:35, from drivers/gpu/drm/mediatek/mtk_drm_debug.c:13: drivers/gpu/drm/mediatek/mtk_drm_debug.c: In function 'mtk_drm_dbg_dump_comp_reg': 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH' 14 | #define KERN_INFO KERN_SOH "6" /* informational */ | ^~~~~~~~ include/linux/printk.h:310:9: note: in expansion of macro 'KERN_INFO' 310 | printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_debug.h:20:31: note: in expansion of macro 'pr_info' 20 | #define mtk_drm_dbg(fmt, ...) pr_info("[mtkdrm] " fmt, ##__VA_ARGS__) | ^~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_debug.c:291:3: note: in expansion of macro 'mtk_drm_dbg' 291 | mtk_drm_dbg("0x%08lX | 0x%08X 0x%08X 0x%08X 0x%08X\n", | ^~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_debug.c:291:22: note: format string is defined here 291 | mtk_drm_dbg("0x%08lX | 0x%08X 0x%08X 0x%08X 0x%08X\n", | ~~~~^ | | | long unsigned int | %08X In file included from include/linux/printk.h:7, from include/linux/kernel.h:14, from include/linux/list.h:9, from include/linux/agp_backend.h:33, from include/drm/drmP.h:35, from drivers/gpu/drm/mediatek/mtk_drm_debug.c:13: drivers/gpu/drm/mediatek/mtk_drm_debug.c: In function 'mtk_drm_dbg_init': 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ include/linux/kern_levels.h:14:19: note: in expansion of macro 'KERN_SOH' 14 | #define KERN_INFO KERN_SOH "6" /* informational */ | ^~~~~~~~ include/linux/printk.h:310:9: note: in expansion of macro 'KERN_INFO' 310 | printk(KERN_INFO pr_fmt(fmt), ##__VA_ARGS__) | ^~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_debug.h:20:31: note: in expansion of macro 'pr_info' 20 | #define mtk_drm_dbg(fmt, ...) pr_info("[mtkdrm] " fmt, ##__VA_ARGS__) | ^~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_debug.c:357:3: note: in expansion of macro 'mtk_drm_dbg' 357 | mtk_drm_dbg("parent node %s\n", dev->of_node->parent->name, | ^~~~~~~~~~~ cc1: all warnings being treated as errors vim +5 include/linux/kern_levels.h 314ba3520e513a Joe Perches 2012-07-30 4 04d2c8c83d0e3a Joe Perches 2012-07-30 @5 #define KERN_SOH "\001" /* ASCII Start Of Header */ 04d2c8c83d0e3a Joe Perches 2012-07-30 6 #define KERN_SOH_ASCII '\001' 04d2c8c83d0e3a Joe Perches 2012-07-30 7 :::::: The code at line 5 was first introduced by commit :::::: 04d2c8c83d0e3ac5f78aeede51babb3236200112 printk: convert the format for KERN_<LEVEL> to a 2 byte pattern :::::: TO: Joe Perches <joe(a)perches.com&gt; :::::: CC: Linus Torvalds <torvalds(a)linux-foundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org