hmm... On Wed, Sep 16, 2020 at 4:48 PM kernel test robot <lkp(a)intel.com&gt; wrote: > > url: https://github.com/0day-ci/linux/commits/Gilad-Ben-Yossef/add-optional-ca... > base: https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git master > config: arm64-randconfig-r015-20200916 (attached as .config) > compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 9e3842d60351f986d77dfe0a94f76e4fd895f188) > 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 > # install arm64 cross compiling tool for clang build > # apt-get install binutils-aarch64-linux-gnu > # save the attached .config to linux build tree > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang 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 warnings (new ones prefixed by >>): > > >> drivers/crypto/ccree/cc_driver.c:120:18: warning: result of comparison of constant 18446744073709551615 with expression of type 'u32' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare] > cache_params |= FIELD_PREP(mask, val); > ^~~~~~~~~~~~~~~~~~~~~ > include/linux/bitfield.h:94:3: note: expanded from macro 'FIELD_PREP' > __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \ > ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/bitfield.h:52:28: note: expanded from macro '__BF_FIELD_CHECK' > BUILD_BUG_ON_MSG((_mask) > (typeof(_reg))~0ull, \ > ~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/build_bug.h:39:58: note: expanded from macro 'BUILD_BUG_ON_MSG' > #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) > ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~ > include/linux/compiler_types.h:319:22: note: expanded from macro 'compiletime_assert' > _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) > ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/compiler_types.h:307:23: note: expanded from macro '_compiletime_assert' > __compiletime_assert(condition, msg, prefix, suffix) > ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > include/linux/compiler_types.h:299:9: note: expanded from macro '__compiletime_assert' > if (!(condition)) \ > ^~~~~~~~~ I am unable to understand this warning. It looks like it is complaining about a FIELD_GET sanity check that is always false, which makes sense since we're using a constant. Anyone can enlighten me if I've missed something?

120 cache_params |= FIELD_PREP(mask, val);