tree: https://android.googlesource.com/kernel/common android-4.19-stable head: a513b1ef96dcd295f77365400c8574d930c7662e commit: c1fae4b2550e30eff0ee060298e18bf94a82df74 [15080/24076] UPSTREAM: Merge remote-tracking branch 'aosp/upstream-f2fs-stable-linux-4.19.y' into android-4.19 (v5.7-rc1) config: i386-randconfig-r036-20210929 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): git remote add android-common https://android.googlesource.com/kernel/common git fetch --no-tags android-common android-4.19-stable git checkout c1fae4b2550e30eff0ee060298e18bf94a82df74 # save the attached .config to linux build tree make W=1 ARCH=i386 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 include/linux/printk.h:7, from include/linux/kernel.h:14, from include/linux/list.h:9, from include/linux/wait.h:7, from include/linux/wait_bit.h:8, from include/linux/fs.h:6, from fs/f2fs/inode.c:8: fs/f2fs/inode.c: In function 'sanity_check_inode': 5 | #define KERN_SOH "\001" /* ASCII Start Of Header */ | ^~~~~~ include/linux/kern_levels.h:12:22: note: in expansion of macro 'KERN_SOH' 12 | #define KERN_WARNING KERN_SOH "4" /* warning conditions */ | ^~~~~~~~ fs/f2fs/f2fs.h:2012:19: note: in expansion of macro 'KERN_WARNING' 2012 | f2fs_printk(sbi, KERN_WARNING fmt, ##__VA_ARGS__) | ^~~~~~~~~~~~ fs/f2fs/inode.c:303:4: note: in expansion of macro 'f2fs_warn' 303 | f2fs_warn(sbi, "%s: inode (ino=%lx) has inconsistent " | ^~~~~~~~~ fs/f2fs/inode.c:304:38: note: format string is defined here 304 | "i_compr_blocks:%llu, i_blocks:%lu, run fsck to fix", | ~~^ | | | long unsigned int | %llu 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