tree: https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git pks/v0.0 head: eed09ce6622d550ab5b10a86e7dd6c2ff6bd59d9 commit: eed09ce6622d550ab5b10a86e7dd6c2ff6bd59d9 [27/27] x86/pks: allow PKS with PTI with __GFP_PTE_MAPPED_2 config: i386-allyesconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git/commit/?id... git remote add rppt https://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux.git git fetch --no-tags rppt pks/v0.0 git checkout eed09ce6622d550ab5b10a86e7dd6c2ff6bd59d9 # save the attached .config to linux build tree make W=1 ARCH=i386 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/x86/mm/pgtable.c:20:12: error: '_pks_unprotect' used but never defined [-Werror] 20 | static int _pks_unprotect(struct page *page, unsigned int cnt); | ^~~~~~~~~~~~~~ 101 | static void __free_table(struct page *table_page, int order) | ^~~~~~~~~~~~ arch/x86/mm/pgtable.c:18:34: error: 'gpc_pks' defined but not used [-Werror=unused-variable] 18 | static struct grouped_page_cache gpc_pks; | ^~~~~~~ cc1: all warnings being treated as errors vim +/__free_table +101 arch/x86/mm/pgtable.c 100 102 { 103 __free_pages(table_page, order); 104 } 105 #endif /* CONFIG_PKS_PG_TABLES */ 106 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org