Hi Catalin, I love your patch! Yet something to improve: [auto build test ERROR on arm-soc/for-next] [also build test ERROR on arm/for-next linus/master v5.6-rc3 next-20200226] [cannot apply to arm64/for-next/core kvmarm/next xlnx/master arm-perf/for-next/perf] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/Catalin-Marinas/arm64-Memory-Tagging-Extension-user-space-support/20200227-041230 base: https://git.kernel.org/pub/scm/linux/kernel/git/arm/arm-soc.git for-next config: x86_64-defconfig (attached as .config) compiler: gcc-7 (Debian 7.5.0-5) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=x86_64 If you fix the issue, kindly add following tag Reported-by: kbuild test robot All error/warnings (new ones prefixed by >>): In file included from include/linux/export.h:43:0, from include/linux/linkage.h:7, from arch/x86/include/asm/cache.h:5, from include/linux/cache.h:6, from include/linux/time.h:5, from include/linux/compat.h:10, from arch/x86/kernel/signal_compat.c:2: In function 'signal_compat_build_tests', inlined from 'sigaction_compat_abi' at arch/x86/kernel/signal_compat.c:166:2: >> include/linux/compiler.h:350:38: error: call to '__compiletime_assert_30' declared with attribute error: BUILD_BUG_ON failed: NSIGSEGV != 7 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^ include/linux/compiler.h:331:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ include/linux/compiler.h:350:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #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' BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) ^~~~~~~~~~~~~~~~ >> arch/x86/kernel/signal_compat.c:30:2: note: in expansion of macro 'BUILD_BUG_ON' BUILD_BUG_ON(NSIGSEGV != 7); ^~~~~~~~~~~~ -- In file included from include/linux/export.h:43:0, from include/linux/linkage.h:7, from arch/x86/include/asm/cache.h:5, from include/linux/cache.h:6, from include/linux/time.h:5, from include/linux/compat.h:10, from arch/x86//kernel/signal_compat.c:2: In function 'signal_compat_build_tests', inlined from 'sigaction_compat_abi' at arch/x86//kernel/signal_compat.c:166:2: >> include/linux/compiler.h:350:38: error: call to '__compiletime_assert_30' declared with attribute error: BUILD_BUG_ON failed: NSIGSEGV != 7 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^ include/linux/compiler.h:331:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ include/linux/compiler.h:350:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:37: note: in expansion of macro 'compiletime_assert' #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' BUILD_BUG_ON_MSG(condition, "BUILD_BUG_ON failed: " #condition) ^~~~~~~~~~~~~~~~ arch/x86//kernel/signal_compat.c:30:2: note: in expansion of macro 'BUILD_BUG_ON' BUILD_BUG_ON(NSIGSEGV != 7); ^~~~~~~~~~~~ vim +/__compiletime_assert_30 +350 include/linux/compiler.h 9a8ab1c39970a4 Daniel Santos 2013-02-21 336 9a8ab1c39970a4 Daniel Santos 2013-02-21 337 #define _compiletime_assert(condition, msg, prefix, suffix) \ 9a8ab1c39970a4 Daniel Santos 2013-02-21 338 __compiletime_assert(condition, msg, prefix, suffix) 9a8ab1c39970a4 Daniel Santos 2013-02-21 339 9a8ab1c39970a4 Daniel Santos 2013-02-21 340 /** 9a8ab1c39970a4 Daniel Santos 2013-02-21 341 * compiletime_assert - break build and emit msg if condition is false 9a8ab1c39970a4 Daniel Santos 2013-02-21 342 * @condition: a compile-time constant condition to check 9a8ab1c39970a4 Daniel Santos 2013-02-21 343 * @msg: a message to emit if condition is false 9a8ab1c39970a4 Daniel Santos 2013-02-21 344 * 9a8ab1c39970a4 Daniel Santos 2013-02-21 345 * In tradition of POSIX assert, this macro will break the build if the 9a8ab1c39970a4 Daniel Santos 2013-02-21 346 * supplied condition is *false*, emitting the supplied error message if the 9a8ab1c39970a4 Daniel Santos 2013-02-21 347 * compiler has support to do so. 9a8ab1c39970a4 Daniel Santos 2013-02-21 348 */ 9a8ab1c39970a4 Daniel Santos 2013-02-21 349 #define compiletime_assert(condition, msg) \ 9a8ab1c39970a4 Daniel Santos 2013-02-21 @350 _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) 9a8ab1c39970a4 Daniel Santos 2013-02-21 351 :::::: The code at line 350 was first introduced by commit :::::: 9a8ab1c39970a4938a72d94e6fd13be88a797590 bug.h, compiler.h: introduce compiletime_assert & BUILD_BUG_ON_MSG :::::: TO: Daniel Santos :::::: CC: Linus Torvalds --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org