Hi Hans, I love your patch! Yet something to improve: [auto build test ERROR on tip/x86/core] [also build test ERROR on v5.6-rc5 next-20200312] [cannot apply to tip/auto-latest bp/for-next] [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/Hans-de-Goede/x86-purgatory-Make... base: https://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git 248ed51048c40d36728e70914e38bffd7821da57 config: x86_64-randconfig-s0-20200312 (attached as .config) compiler: gcc-5 (Ubuntu 5.5.0-12ubuntu1) 5.5.0 20171010 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 <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): ld: arch/x86/purgatory/purgatory.ro: in function `_GLOBAL__sub_I_65535_0_purgatory': ld: arch/x86/purgatory/purgatory.ro: in function `_GLOBAL__sub_I_65535_0_sha256_update': ld: arch/x86/purgatory/purgatory.ro: in function `_GLOBAL__sub_I_65535_0_memcmp': ld: arch/x86/purgatory/purgatory.ro:(.data+0xc0): undefined reference to `__gcov_merge_add' ld: arch/x86/purgatory/purgatory.ro:(.data+0x21e0): undefined reference to `__gcov_merge_add' ld: arch/x86/purgatory/purgatory.ro:(.data+0x2780): undefined reference to `__gcov_merge_add' vim +287 lib/crypto/sha256.c 9ecf5ad522e09d Hans de Goede 2019-08-25 286 9ecf5ad522e09d Hans de Goede 2019-08-25 @287 MODULE_LICENSE("GPL"); :::::: The code at line 287 was first introduced by commit :::::: 9ecf5ad522e09d6e11a7e0a0b1845622a480f478 crypto: sha256 - Add missing MODULE_LICENSE() to lib/crypto/sha256.c :::::: TO: Hans de Goede <hdegoede(a)redhat.com&gt; :::::: CC: Herbert Xu <herbert(a)gondor.apana.org.au&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org