tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.14.y head: e1f7d50ae3a3ec342e87a9b1ce6787bfb8b3c08b commit: 27647dde3018985379d58feacf2fc3f11e91b478 [9243/9999] proc/vmcore: Fix i386 build error of missing copy_oldmem_page_encrypted() config: mips-randconfig-r005-20200809 (attached as .config) compiler: mipsel-linux-gcc (GCC) 9.3.0 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 git checkout 27647dde3018985379d58feacf2fc3f11e91b478 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=mips 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 >>): In file included from include/linux/workqueue.h:9, from include/linux/srcu.h:34, from include/linux/notifier.h:16, from include/linux/memory_hotplug.h:7, from include/linux/mmzone.h:782, from include/linux/gfp.h:6, from include/linux/mm.h:10, from fs/proc/vmcore.c:10: include/linux/timer.h: In function 'timer_setup': include/linux/timer.h:179:23: warning: cast between incompatible function types from 'void (*)(struct timer_list *)' to 'void (*)(long unsigned int)' [-Wcast-function-type] 179 | __setup_timer(timer, (TIMER_FUNC_TYPE)callback, | ^ include/linux/timer.h:144:25: note: in definition of macro '__setup_timer' 144 | (_timer)->function = (_fn); \ | ^~~ fs/proc/vmcore.c: At top level: 171 | copy_oldmem_page_encrypted(unsigned long pfn, char *buf, size_t csize, | ^~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/copy_oldmem_page_encrypted +171 fs/proc/vmcore.c 166 167 /* 168 * Architectures which support memory encryption override this. 169 */ 170 ssize_t __weak 172 unsigned long offset, int userbuf) 173 { 174 return copy_oldmem_page(pfn, buf, csize, offset, userbuf); 175 } 176 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org