Hi, [auto build test WARNING on char-misc/char-misc-testing] [also build test WARNING on v4.7-rc2 next-20160607] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system]
url: https://github.com/0day-ci/linux/commits/Kees-Cook/lkdtm-add-usercopy-and-rodata-fix-atomic/20160608-060444 config: s390-default_defconfig (attached as .config) compiler: s390x-linux-gnu-gcc (Debian 5.3.1-8) 5.3.1 20160205 reproduce: wget https://git.kernel.org/cgit/linux/kernel/git/wfg/lkp-tests.git/plain/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree make.cross ARCH=s390 All warnings (new ones prefixed by >>): drivers/misc/lkdtm_core.c: In function 'do_usercopy_stack_callee.isra.0': >> drivers/misc/lkdtm_core.c:420:9: warning: function returns address of local >> variable [-Wreturn-local-addr] return ptr; ^ drivers/misc/lkdtm_core.c:405:16: note: declared here unsigned char buf[32]; ^ vim +420 drivers/misc/lkdtm_core.c 404 { 405 unsigned char buf[32]; 406 unsigned char *ptr = NULL; 407 int i; 408 409 /* Exercise stack to avoid everything living in registers. */ 410 for (i = 0; i < sizeof(buf); i++) { 411 /* 412 * Hack to trick gcc into letting us return a reference 413 * to a local stack frame. 414 */ 415 if (i == 0) 416 ptr = buf; 417 buf[i] = value & 0xff; 418 } 419 > 420 return ptr; 421 } 422 423 static noinline void do_usercopy_stack(bool to_user) 424 { 425 unsigned long user_addr; 426 unsigned char good_stack[32]; 427 unsigned char *bad_stack; 428 int i; --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
.config.gz
Description: Binary data
