tree: git://github.com/davidhildenbrand/linux foll_unshare head: f4b54ddc31ca94dedc57a3aab1f42d348537a31b commit: f270db76384cb1df5a7f1b67226a8c8515583e5f [1/2] seqlock: provide lockdep-free raw_seqcount_t variant config: riscv-buildonly-randconfig-r003-20211207 (https://download.01.org/0day-ci/archive/20211209/202112090736.d9HFdWOz-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 097a1cb1d5ebb3a0ec4bcaed8ba3ff6a8e33c00a) 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 riscv cross compiling tool for clang build # apt-get install binutils-riscv64-linux-gnu # https://github.com/davidhildenbrand/linux/commit/f270db76384cb1df5a7f1b67... git remote add davidhildenbrand git://github.com/davidhildenbrand/linux git fetch --no-tags davidhildenbrand foll_unshare git checkout f270db76384cb1df5a7f1b67226a8c8515583e5f # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=riscv SHELL=/bin/bash net/phonet/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from net/phonet/sysctl.c:17: In file included from include/net/sock.h:38: In file included from include/linux/hardirq.h:11: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:136: 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/little_endian.h:36:51: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) ^ In file included from net/phonet/sysctl.c:17: In file included from include/net/sock.h:38: In file included from include/linux/hardirq.h:11: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:136: 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/little_endian.h:34:51: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) ^ In file included from net/phonet/sysctl.c:17: In file included from include/net/sock.h:38: In file included from include/linux/hardirq.h:11: In file included from ./arch/riscv/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/riscv/include/asm/io.h:136: 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:1024:55: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] return (port > MMIO_UPPER_LIMIT) ? NULL : PCI_IOBASE + port; ~~~~~~~~~~ ^ static DEFINE_SEQLOCK(local_port_range_lock); ^ include/linux/seqlock.h:907:18: note: expanded from macro 'DEFINE_SEQLOCK' seqlock_t sl = __SEQLOCK_UNLOCKED(sl) ^ include/linux/seqlock.h:888:15: note: expanded from macro '__SEQLOCK_UNLOCKED' .seqcount = SEQCNT_SPINLOCK_ZERO(lockname, &(lockname).lock), \ ^ include/linux/seqlock.h:358:42: note: expanded from macro 'SEQCNT_SPINLOCK_ZERO' #define SEQCNT_SPINLOCK_ZERO(name, lock) SEQCOUNT_LOCKNAME_ZERO(name, lock) ^ include/linux/seqlock.h:353:15: note: expanded from macro 'SEQCOUNT_LOCKNAME_ZERO' .seqcount = SEQCNT_ZERO(seq_name.seqcount), \ ^ include/linux/seqlock.h:141:30: note: expanded from macro 'SEQCNT_ZERO' #define SEQCNT_ZERO(name) { .seqcount = RAW_SEQCNT_ZERO(), SEQCOUNT_DEP_MAP_INIT(name) } ^ 7 warnings and 1 error generated. vim +24 net/phonet/sysctl.c 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 23 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 @24 static DEFINE_SEQLOCK(local_port_range_lock); 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 25 static int local_port_range_min[2] = {0, 0}; 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 26 static int local_port_range_max[2] = {1023, 1023}; 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 27 static int local_port_range[2] = {DYNAMIC_PORT_MIN, DYNAMIC_PORT_MAX}; 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 28 static struct ctl_table_header *phonet_table_hrd; 87ab4e20b445c6d Remi Denis-Courmont 2008-09-22 29 :::::: The code at line 24 was first introduced by commit :::::: 87ab4e20b445c6d2d2727ab4f96fa17f7259511e Phonet: proc interface for port range :::::: TO: Remi Denis-Courmont <remi.denis-courmont(a)nokia.com&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org