Hi Deven, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on dm/for-next] [also build test WARNING on pcmoore-selinux/next linus/master v5.8-rc5] [cannot apply to security/next-testing next-20200717] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Deven-Bowers/Integrity-Policy-En... base: https://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm.git for-next config: s390-randconfig-r015-20200717 (attached as .config) compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project ed6b578040a85977026c93bf4188f996148f3218) 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 # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390 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 >>): include/asm-generic/io.h:490:45: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ include/uapi/linux/swab.h:21:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0x00ff0000UL) >> 8) | \ ^ In file included from drivers/md/dm-verity-target.c:16: In file included from drivers/md/dm-verity.h:14: In file included from include/linux/dm-bufio.h:12: In file included from include/linux/blkdev.h:28: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:72: include/asm-generic/io.h:490:45: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32' ___constant_swab32(x) : \ ^ include/uapi/linux/swab.h:22:12: note: expanded from macro '___constant_swab32' (((__u32)(x) & (__u32)0xff000000UL) >> 24))) ^ In file included from drivers/md/dm-verity-target.c:16: In file included from drivers/md/dm-verity.h:14: In file included from include/linux/dm-bufio.h:12: In file included from include/linux/blkdev.h:28: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:72: include/asm-generic/io.h:490:45: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu(__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:34:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:120:12: note: expanded from macro '__swab32' __fswab32(x)) ^ In file included from drivers/md/dm-verity-target.c:16: In file included from drivers/md/dm-verity.h:14: In file included from include/linux/dm-bufio.h:12: In file included from include/linux/blkdev.h:28: In file included from include/linux/scatterlist.h:9: In file included from arch/s390/include/asm/io.h:72: include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:511:46: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew(cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:521:46: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel(cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ In file included from drivers/md/dm-verity-target.c:18: drivers/md/dm-verity-verify-sig.h:37:5: warning: no previous prototype for function 'verity_verify_root_hash' [-Wmissing-prototypes] int verity_verify_root_hash(const struct dm_verity *v) ^ drivers/md/dm-verity-verify-sig.h:37:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int verity_verify_root_hash(const struct dm_verity *v) ^ static drivers/md/dm-verity-verify-sig.h:42:6: warning: no previous prototype for function 'verity_verify_is_sig_opt_arg' [-Wmissing-prototypes] bool verity_verify_is_sig_opt_arg(const char *arg_name) ^ drivers/md/dm-verity-verify-sig.h:42:1: note: declare 'static' if the function is not intended to be used outside of this translation unit bool verity_verify_is_sig_opt_arg(const char *arg_name) ^ static drivers/md/dm-verity-verify-sig.h:47:5: warning: no previous prototype for function 'verity_verify_sig_parse_opt_args' [-Wmissing-prototypes] int verity_verify_sig_parse_opt_args(struct dm_arg_set *as, struct dm_verity *v, ^ drivers/md/dm-verity-verify-sig.h:47:1: note: declare 'static' if the function is not intended to be used outside of this translation unit int verity_verify_sig_parse_opt_args(struct dm_arg_set *as, struct dm_verity *v, ^ static void verity_verify_dtr(struct dm_verity *v) ^ drivers/md/dm-verity-verify-sig.h:53:1: note: declare 'static' if the function is not intended to be used outside of this translation unit void verity_verify_dtr(struct dm_verity *v) ^ static 24 warnings generated. vim +/verity_verify_dtr +53 drivers/md/dm-verity-verify-sig.h 46 48 unsigned int *argc) 49 { 50 return -EINVAL; 51 } 52 54 { 55 } 56 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org