tree: https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git for-5.14/io_uring head: aeab9506ef50d23b350d1822c324023c9e1cb783 commit: 9123c8ffce1610323ec9c0874fa0262353f41fc3 [24/28] io_uring: add helpers for 2 level table alloc config: powerpc64-randconfig-r016-20210613 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 64720f57bea6a6bf033feef4a5751ab9c0c3b401) 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 powerpc64 cross compiling tool for clang build # apt-get install binutils-powerpc64-linux-gnu # https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git/com... git remote add block https://git.kernel.org/pub/scm/linux/kernel/git/axboe/linux-block.git git fetch --no-tags block for-5.14/io_uring git checkout 9123c8ffce1610323ec9c0874fa0262353f41fc3 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc64 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 arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:45:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insw, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:247:1: note: expanded from here __do_insw ^ arch/powerpc/include/asm/io.h:557:56: note: expanded from macro '__do_insw' #define __do_insw(p, b, n) readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from fs/io_uring.c:45: In file included from include/linux/syscalls.h:87: In file included from include/trace/syscall.h:7: In file included from include/linux/trace_events.h:9: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:47:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:249:1: note: expanded from here __do_insl ^ arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl' #define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from fs/io_uring.c:45: In file included from include/linux/syscalls.h:87: In file included from include/trace/syscall.h:7: In file included from include/linux/trace_events.h:9: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:49:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:251:1: note: expanded from here __do_outsb ^ arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb' #define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from fs/io_uring.c:45: In file included from include/linux/syscalls.h:87: In file included from include/trace/syscall.h:7: In file included from include/linux/trace_events.h:9: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:51:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:253:1: note: expanded from here __do_outsw ^ arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw' #define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from fs/io_uring.c:45: In file included from include/linux/syscalls.h:87: In file included from include/trace/syscall.h:7: In file included from include/linux/trace_events.h:9: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:53:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:255:1: note: expanded from here __do_outsl ^ arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl' #define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ unsigned int this_size = min(size, PAGE_SIZE); ^~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:45:19: note: expanded from macro 'min' #define min(x, y) __careful_cmp(x, y, <) ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' __builtin_choose_expr(__safe_cmp(x, y), \ ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' (__typecheck(x, y) && __no_side_effects(x, y)) ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ 8 warnings generated. vim +7082 fs/io_uring.c 7070 7071 static void **io_alloc_page_table(size_t size) 7072 { 7073 unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE); 7074 size_t init_size = size; 7075 void **table; 7076 7077 table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL); 7078 if (!table) 7079 return NULL; 7080 7081 for (i = 0; i < nr_tables; i++) { 7083 7084 table[i] = kzalloc(this_size, GFP_KERNEL); 7085 if (!table[i]) { 7086 io_free_page_table(table, init_size); 7087 return NULL; 7088 } 7089 size -= this_size; 7090 } 7091 return table; 7092 } 7093 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org