Hi Bibo, kernel test robot noticed the following build warnings: [auto build test WARNING on 87d6aab2389e5ce0197d8257d5f8ee965a67c4cd] url: https://github.com/intel-lab-lkp/linux/commits/Bibo-Mao/LoongArch-Set-pte-entry-with-PAGE_GLOBAL-for-kernel-space/20241010-115120 base: 87d6aab2389e5ce0197d8257d5f8ee965a67c4cd patch link: https://lore.kernel.org/r/20241010035048.3422527-3-maobibo%40loongson.cn patch subject: [PATCH 2/4] mm/sparse-vmemmap: set pte_init when vmemmap is created config: s390-allnoconfig (https://download.01.org/0day-ci/archive/20241011/202410111254.kon5pPzX-lkp@xxxxxxxxx/config) compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 70e0a7e7e6a8541bcc46908c592eed561850e416) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20241011/202410111254.kon5pPzX-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202410111254.kon5pPzX-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from mm/sparse-vmemmap.c:21: In file included from include/linux/mm.h:2213: include/linux/vmstat.h:518:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 518 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ In file included from mm/sparse-vmemmap.c:23: In file included from include/linux/memblock.h:13: In file included from arch/s390/include/asm/dma.h:5: In file included from include/linux/io.h:14: In file included from arch/s390/include/asm/io.h:93: include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 548 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) | ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' 102 | #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) | ^ In file included from mm/sparse-vmemmap.c:23: In file included from include/linux/memblock.h:13: In file included from arch/s390/include/asm/dma.h:5: In file included from include/linux/io.h:14: In file included from arch/s390/include/asm/io.h:93: include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) | ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' 115 | #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) | ^ In file included from mm/sparse-vmemmap.c:23: In file included from include/linux/memblock.h:13: In file included from arch/s390/include/asm/dma.h:5: In file included from include/linux/io.h:14: In file included from arch/s390/include/asm/io.h:93: include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 585 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:693:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 693 | readsb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:701:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 701 | readsw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:709:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 709 | readsl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:718:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 718 | writesb(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:727:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 727 | writesw(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ include/asm-generic/io.h:736:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 736 | writesl(PCI_IOBASE + addr, buffer, count); | ~~~~~~~~~~ ^ >> mm/sparse-vmemmap.c:187:23: warning: no previous prototype for function 'kernel_pte_init' [-Wmissing-prototypes] 187 | void __weak __meminit kernel_pte_init(void *addr) | ^ mm/sparse-vmemmap.c:187:1: note: declare 'static' if the function is not intended to be used outside of this translation unit 187 | void __weak __meminit kernel_pte_init(void *addr) | ^ | static 14 warnings generated. vim +/kernel_pte_init +187 mm/sparse-vmemmap.c 186 > 187 void __weak __meminit kernel_pte_init(void *addr) 188 { 189 } 190 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki