Hi Vineet, I love your patch! Yet something to improve: [auto build test ERROR on arc/for-next] [also build test ERROR on linux/master linus/master v5.14-rc5 next-20210812] [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/Vineet-Gupta/ARC-mm-updates-supp... base: https://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc.git for-next config: arc-randconfig-s032-20210812 (attached as .config) compiler: arceb-elf-gcc (GCC) 10.3.0 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: v0.6.3-348-gf0e6938b-dirty # https://github.com/0day-ci/linux/commit/36e618e081c5a49b2aff51823c5f01204... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Vineet-Gupta/ARC-mm-updates-support-3-4-levels-and-asm-generic-pgalloc/20210813-074023 git checkout 36e618e081c5a49b2aff51823c5f012045e902ef # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arc 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 >>): arch/arc/mm/init.c:35:13: warning: no previous prototype for 'arc_get_mem_sz' [-Wmissing-prototypes] 35 | long __init arc_get_mem_sz(void) | ^~~~~~~~~~~~~~ arch/arc/mm/init.c:88:13: warning: no previous prototype for 'setup_arch_memory' [-Wmissing-prototypes] 88 | void __init setup_arch_memory(void) | ^~~~~~~~~~~~~~~~~ In file included from <command-line>: arch/arc/mm/init.c: In function 'mem_init': 328 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^ include/linux/compiler_types.h:309:4: note: in definition of macro '__compiletime_assert' 309 | prefix ## suffix(); \ | ^~~~~~ include/linux/compiler_types.h:328:2: note: in expansion of macro '_compiletime_assert' 328 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) | ^~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:50:2: note: in expansion of macro 'BUILD_BUG_ON_MSG' 50 | BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) | ^~~~~~~~~~~~~~~~ arch/arc/mm/init.c:193:2: note: in expansion of macro 'BUILD_BUG_ON' 193 | BUILD_BUG_ON((PTRS_PER_PGD * sizeof(pgd_t)) > PAGE_SIZE); | ^~~~~~~~~~~~ vim +/__compiletime_assert_328 +328 include/linux/compiler_types.h eb5c2d4b45e3d2 Will Deacon 2020-07-21 314 eb5c2d4b45e3d2 Will Deacon 2020-07-21 315 #define _compiletime_assert(condition, msg, prefix, suffix) \ eb5c2d4b45e3d2 Will Deacon 2020-07-21 316 __compiletime_assert(condition, msg, prefix, suffix) eb5c2d4b45e3d2 Will Deacon 2020-07-21 317 eb5c2d4b45e3d2 Will Deacon 2020-07-21 318 /** eb5c2d4b45e3d2 Will Deacon 2020-07-21 319 * compiletime_assert - break build and emit msg if condition is false eb5c2d4b45e3d2 Will Deacon 2020-07-21 320 * @condition: a compile-time constant condition to check eb5c2d4b45e3d2 Will Deacon 2020-07-21 321 * @msg: a message to emit if condition is false eb5c2d4b45e3d2 Will Deacon 2020-07-21 322 * eb5c2d4b45e3d2 Will Deacon 2020-07-21 323 * In tradition of POSIX assert, this macro will break the build if the eb5c2d4b45e3d2 Will Deacon 2020-07-21 324 * supplied condition is *false*, emitting the supplied error message if the eb5c2d4b45e3d2 Will Deacon 2020-07-21 325 * compiler has support to do so. eb5c2d4b45e3d2 Will Deacon 2020-07-21 326 */ eb5c2d4b45e3d2 Will Deacon 2020-07-21 327 #define compiletime_assert(condition, msg) \ eb5c2d4b45e3d2 Will Deacon 2020-07-21 @328 _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) eb5c2d4b45e3d2 Will Deacon 2020-07-21 329 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org