tree: https://github.com/intel/linux-intel-lts.git 5.10/yocto head: 26a890b883303c93193cca69d5a096f550f93c6d commit: 26a890b883303c93193cca69d5a096f550f93c6d [3/3] igc: Add support for DMA timestamp for non-PTP packets config: s390-randconfig-r014-20210709 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 8d69635ed9ecf36fd0ca85906bfde17949671cbe) 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 # https://github.com/intel/linux-intel-lts/commit/26a890b883303c93193cca69d... git remote add intel-linux-intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-linux-intel-lts 5.10/yocto git checkout 26a890b883303c93193cca69d5a096f550f93c6d # 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 >>): In file included from drivers/net/ethernet/intel/igc/igc_ptp.c:4: In file included from drivers/net/ethernet/intel/igc/igc.h:8: In file included from include/linux/pci.h:39: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:36:59: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) ^ In file included from drivers/net/ethernet/intel/igc/igc_ptp.c:4: In file included from drivers/net/ethernet/intel/igc/igc.h:8: In file included from include/linux/pci.h:39: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__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:115:54: note: expanded from macro '__swab32' #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) ^ In file included from drivers/net/ethernet/intel/igc/igc_ptp.c:4: In file included from drivers/net/ethernet/intel/igc/igc.h:8: In file included from include/linux/pci.h:39: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:80: 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:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)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); ~~~~~~~~~~ ^ u32 sec, nsec; ^ 13 warnings generated. vim +/nsec +438 drivers/net/ethernet/intel/igc/igc_ptp.c 432 433 static void igc_ptp_dma_time_to_hwtstamp(struct igc_adapter *adapter, 434 struct skb_shared_hwtstamps *hwtstamps, 435 u64 systim) 436 { 437 struct igc_hw *hw = &adapter->hw; 439 440 /* FIXME: use a workqueue to read these values to avoid 441 * reading these registers in the hot path. 442 */ 443 nsec = rd32(IGC_SYSTIML); 444 sec = rd32(IGC_SYSTIMH); 445 446 switch (adapter->hw.mac.type) { 447 case igc_i225: 448 memset(hwtstamps, 0, sizeof(*hwtstamps)); 449 450 /* HACK */ 451 hwtstamps->hwtstamp = ktime_set(sec, systim & 0xFFFFFFFF); 452 break; 453 default: 454 break; 455 } 456 } 457 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org