Hi Peter, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on akpm-mm/mm-everything] [also build test WARNING on next-20220928] [cannot apply to arm64/for-next/core linus/master v6.0-rc7] [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#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Peter-Collingbourne/kasan-also-display-registers-for-reports-from-HW-exceptions/20220927-092847 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything config: powerpc-randconfig-r006-20220925 compiler: clang version 16.0.0 (https://github.com/llvm/llvm-project 791a7ae1ba3efd6bca96338e10ffde557ba83920) 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 powerpc cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/intel-lab-lkp/linux/commit/010a23f5998ecdcc86e8dd37393862861dbd7e55 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Peter-Collingbourne/kasan-also-display-registers-for-reports-from-HW-exceptions/20220927-092847 git checkout 010a23f5998ecdcc86e8dd37393862861dbd7e55 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=powerpc SHELL=/bin/bash mm/kasan/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot 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:640: 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:637:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ :182:1: note: expanded from here __do_insw ^ arch/powerpc/include/asm/io.h:578:56: 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 mm/kasan/report.c:13: In file included from include/linux/ftrace.h:10: In file included from include/linux/trace_recursion.h:5: In file included from include/linux/interrupt.h:11: 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:640: 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:637:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ :184:1: note: expanded from here __do_insl ^ arch/powerpc/include/asm/io.h:579:56: 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 mm/kasan/report.c:13: In file included from include/linux/ftrace.h:10: In file included from include/linux/trace_recursion.h:5: In file included from include/linux/interrupt.h:11: 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:640: 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:637:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ :186:1: note: expanded from here __do_outsb ^ arch/powerpc/include/asm/io.h:580:58: 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 mm/kasan/report.c:13: In file included from include/linux/ftrace.h:10: In file included from include/linux/trace_recursion.h:5: In file included from include/linux/interrupt.h:11: 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:640: 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:637:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ :188:1: note: expanded from here __do_outsw ^ arch/powerpc/include/asm/io.h:581:58: 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 mm/kasan/report.c:13: In file included from include/linux/ftrace.h:10: In file included from include/linux/trace_recursion.h:5: In file included from include/linux/interrupt.h:11: 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:640: 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:637:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ :190:1: note: expanded from here __do_outsl ^ arch/powerpc/include/asm/io.h:582:58: note: expanded from macro '__do_outsl' #define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ >> mm/kasan/report.c:514:6: warning: no previous prototype for function 'kasan_report_regs' [-Wmissing-prototypes] bool kasan_report_regs(unsigned long addr, size_t size, bool is_write, ^ mm/kasan/report.c:514:1: note: declare 'static' if the function is not intended to be used outside of this translation unit bool kasan_report_regs(unsigned long addr, size_t size, bool is_write, ^ static 7 warnings generated. Kconfig warnings: (for reference only) WARNING: unmet direct dependencies detected for PROC_CHILDREN Depends on [n]: PROC_FS [=n] Selected by [y]: - CHECKPOINT_RESTORE [=y] vim +/kasan_report_regs +514 mm/kasan/report.c 513 > 514 bool kasan_report_regs(unsigned long addr, size_t size, bool is_write, 515 struct pt_regs *regs) 516 { 517 return __kasan_report(addr, size, is_write, instruction_pointer(regs), 518 regs); 519 } 520 -- 0-DAY CI Kernel Test Service https://01.org/lkp