Hi Chris, I love your patch! Yet something to improve: [auto build test ERROR on jeyu/modules-next] [also build test ERROR on linux/master soc/for-next openrisc/for-next powerpc/next uml/linux-next asm-generic/master driver-core/driver-core-testing linus/master v5.13-rc6 next-20210617] [cannot apply to tip/x86/core] [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] url: https://github.com/0day-ci/linux/commits/Chris-Down/printk-Userspace-form... base: https://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux.git modules-next config: ia64-randconfig-s031-20210618 (attached as .config) compiler: ia64-linux-gcc (GCC) 9.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.3-341-g8af24329-dirty # https://github.com/0day-ci/linux/commit/819166a91ddffdbf04d0b4e6905a5ab3b... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Chris-Down/printk-Userspace-format-indexing-support/20210617-101450 git checkout 819166a91ddffdbf04d0b4e6905a5ab3b568194f # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' W=1 ARCH=ia64 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/kernel.h:17, from include/asm-generic/bug.h:20, from arch/ia64/include/asm/bug.h:17, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: 219 | int _printk(const char *s, ...) | ^~~~~~~ In file included from arch/ia64/include/uapi/asm/intrinsics.h:22, from arch/ia64/include/asm/intrinsics.h:11, from arch/ia64/include/asm/bitops.h:19, from include/linux/bitops.h:32, from include/linux/kernel.h:12, from include/asm-generic/bug.h:20, from arch/ia64/include/asm/bug.h:17, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: arch/ia64/include/uapi/asm/cmpxchg.h:142:14: note: previous declaration of '_printk' was here 142 | extern int _printk(const char *fmt, ...); \ | ^~~~~~~ arch/ia64/include/asm/bitops.h:309:3: note: in expansion of macro 'CMPXCHG_BUGCHECK' 309 | CMPXCHG_BUGCHECK(m); | ^~~~~~~~~~~~~~~~ -- In file included from include/linux/kernel.h:17, from include/asm-generic/bug.h:20, from arch/ia64/include/asm/bug.h:17, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: 219 | int _printk(const char *s, ...) | ^~~~~~~ In file included from arch/ia64/include/uapi/asm/intrinsics.h:22, from arch/ia64/include/asm/intrinsics.h:11, from arch/ia64/include/asm/bitops.h:19, from include/linux/bitops.h:32, from include/linux/kernel.h:12, from include/asm-generic/bug.h:20, from arch/ia64/include/asm/bug.h:17, from include/linux/bug.h:5, from include/linux/page-flags.h:10, from kernel/bounds.c:10: arch/ia64/include/uapi/asm/cmpxchg.h:142:14: note: previous declaration of '_printk' was here 142 | extern int _printk(const char *fmt, ...); \ | ^~~~~~~ arch/ia64/include/asm/bitops.h:309:3: note: in expansion of macro 'CMPXCHG_BUGCHECK' 309 | CMPXCHG_BUGCHECK(m); | ^~~~~~~~~~~~~~~~ make[2]: *** [scripts/Makefile.build:117: kernel/bounds.s] Error 1 make[2]: Target '__build' not remade because of errors. make[1]: *** [Makefile:1227: prepare0] Error 2 make[1]: Target 'prepare' not remade because of errors. make: *** [Makefile:215: __sub-make] Error 2 make: Target 'prepare' not remade because of errors. vim +/_printk +219 include/linux/printk.h 201 202 char *log_buf_addr_get(void); 203 u32 log_buf_len_get(void); 204 void log_buf_vmcoreinfo_setup(void); 205 void __init setup_log_buf(int early); 206 __printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...); 207 void dump_stack_print_info(const char *log_lvl); 208 void show_regs_print_info(const char *log_lvl); 209 extern asmlinkage void dump_stack(void) __cold; 210 extern void printk_safe_flush(void); 211 extern void printk_safe_flush_on_panic(void); 212 #else 213 static inline __printf(1, 0) 214 int vprintk(const char *s, va_list args) 215 { 216 return 0; 217 } 218 static inline __printf(1, 2) __cold 220 { 221 return 0; 222 } 223 static inline __printf(1, 2) __cold 224 int _printk_deferred(const char *s, ...) 225 { 226 return 0; 227 } 228 static inline int printk_ratelimit(void) 229 { 230 return 0; 231 } 232 static inline bool printk_timed_ratelimit(unsigned long *caller_jiffies, 233 unsigned int interval_msec) 234 { 235 return false; 236 } 237 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org