Hi "Matthew, Thank you for the patch! Yet something to improve: [auto build test ERROR on linus/master] [also build test ERROR on v5.14-rc1 next-20210715] [cannot apply to hnaz-linux-mm/master xfs-linux/for-next tip/perf/core] [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] url: https://github.com/0day-ci/linux/commits/Matthew-Wilcox-Oracle/Memory-fol... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8096acd7442e613fad0354fc8dfdb2003cceea0b config: powerpc-randconfig-r033-20210715 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project 0e49c54a8cbd3e779e5526a5888c683c01cc3c50) 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/0day-ci/linux/commit/8e4044529261dffc386ab56b6d90e8511... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Matthew-Wilcox-Oracle/Memory-folios/20210715-133101 git checkout 8e4044529261dffc386ab56b6d90e8511c820605 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=powerpc 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 include/linux/pagemap.h:11: In file included from include/linux/highmem.h:10: 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: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>:16:1: 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/netfs/read_helper.c:12: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:10: 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>:20:1: 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/netfs/read_helper.c:12: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:10: 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>:24:1: 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/netfs/read_helper.c:12: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:10: 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>:28:1: 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/netfs/read_helper.c:12: In file included from include/linux/pagemap.h:11: In file included from include/linux/highmem.h:10: 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>:32:1: 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)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from fs/netfs/read_helper.c:17: folio_set_private_2_flag(folio); ^ include/linux/netfs.h:43:2: note: did you mean 'folio_set_private_2'? include/linux/page-flags.h:445:1: note: 'folio_set_private_2' declared here PAGEFLAG(Private2, private_2, PF_ANY) TESTSCFLAG(Private2, private_2, PF_ANY) ^ include/linux/page-flags.h:362:2: note: expanded from macro 'PAGEFLAG' SETPAGEFLAG(uname, lname, policy) \ ^ include/linux/page-flags.h:320:6: note: expanded from macro 'SETPAGEFLAG' void folio_set_##lname(struct folio *folio) \ ^ <scratch space>:70:1: note: expanded from here folio_set_private_2 ^ 12 warnings and 1 error generated. vim +/folio_set_private_2_flag +43 include/linux/netfs.h 31 32 /** 33 * folio_start_fscache - Start an fscache write on a folio. 34 * @folio: The folio. 35 * 36 * Call this function before writing a folio to a local cache. Starting a 37 * second write before the first one finishes is not allowed. 38 */ 39 static inline void folio_start_fscache(struct folio *folio) 40 { 41 VM_BUG_ON_FOLIO(folio_test_private_2(folio), folio); 42 folio_get(folio); 44 } 45 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org