Hi Matthew, kernel test robot noticed the following build warnings: [auto build test WARNING on akpm-mm/mm-everything] [also build test WARNING on linus/master v6.4-rc6] [cannot apply to next-20230614] [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/Matthew-Wilcox-Oracle/highmem-Add-memcpy_from_folio/20230614-215150 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20230614134853.1521439-1-willy%40infradead.org patch subject: [PATCH 1/2] highmem: Add memcpy_to_folio() config: hexagon-randconfig-r015-20230614 (https://download.01.org/0day-ci/archive/20230615/202306150241.f2mNsWXE-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a) reproduce (this is a W=1 build): mkdir -p ~/bin wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git remote add akpm-mm https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git git fetch akpm-mm mm-everything git checkout akpm-mm/mm-everything b4 shazam https://lore.kernel.org/r/20230614134853.1521439-1-willy@xxxxxxxxxxxxx # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/nvme/target/ 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/202306150241.f2mNsWXE-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/nvme/target/fc.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/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/hexagon/include/asm/io.h:334: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 547 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from drivers/nvme/target/fc.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/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/hexagon/include/asm/io.h:334: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from drivers/nvme/target/fc.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: In file included from include/linux/highmem.h:12: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/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/hexagon/include/asm/io.h:334: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 584 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ In file included from drivers/nvme/target/fc.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: >> include/linux/highmem.h:525:7: warning: comparison of distinct pointer types ('typeof (len) *' (aka 'unsigned int *') and 'typeof ((1UL << 12) - ((unsigned long)(offset) & ~(~((1 << 12) - 1)))) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types] 525 | n = min(len, PAGE_SIZE - offset_in_page(offset)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:67:19: note: expanded from macro 'min' 67 | #define min(x, y) __careful_cmp(x, y, <) | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' 36 | __builtin_choose_expr(__safe_cmp(x, y), \ | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' 26 | (__typecheck(x, y) && __no_side_effects(x, y)) | ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' 20 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ In file included from drivers/nvme/target/fc.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: >> include/linux/highmem.h:534:7: warning: comparison of distinct pointer types ('typeof (len) *' (aka 'unsigned int *') and 'typeof ((1UL << 12)) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types] 534 | n = min(len, PAGE_SIZE); | ^~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:67:19: note: expanded from macro 'min' 67 | #define min(x, y) __careful_cmp(x, y, <) | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' 36 | __builtin_choose_expr(__safe_cmp(x, y), \ | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' 26 | (__typecheck(x, y) && __no_side_effects(x, y)) | ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' 20 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ drivers/nvme/target/fc.c:176:1: warning: unused function 'nvmet_fc_iodnum' [-Wunused-function] 176 | nvmet_fc_iodnum(struct nvmet_fc_ls_iod *iodptr) | ^ drivers/nvme/target/fc.c:182:1: warning: unused function 'nvmet_fc_fodnum' [-Wunused-function] 182 | nvmet_fc_fodnum(struct nvmet_fc_fcp_iod *fodptr) | ^ 10 warnings generated. -- In file included from drivers/nvme/target/loop.c:7: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 547 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from drivers/nvme/target/loop.c:7: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from drivers/nvme/target/loop.c:7: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 584 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ In file included from drivers/nvme/target/loop.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: >> include/linux/highmem.h:525:7: warning: comparison of distinct pointer types ('typeof (len) *' (aka 'unsigned int *') and 'typeof ((1UL << 12) - ((unsigned long)(offset) & ~(~((1 << 12) - 1)))) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types] 525 | n = min(len, PAGE_SIZE - offset_in_page(offset)); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:67:19: note: expanded from macro 'min' 67 | #define min(x, y) __careful_cmp(x, y, <) | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' 36 | __builtin_choose_expr(__safe_cmp(x, y), \ | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' 26 | (__typecheck(x, y) && __no_side_effects(x, y)) | ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' 20 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ In file included from drivers/nvme/target/loop.c:8: In file included from include/linux/blk-mq.h:5: In file included from include/linux/blkdev.h:9: In file included from include/linux/blk_types.h:10: In file included from include/linux/bvec.h:10: >> include/linux/highmem.h:534:7: warning: comparison of distinct pointer types ('typeof (len) *' (aka 'unsigned int *') and 'typeof ((1UL << 12)) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types] 534 | n = min(len, PAGE_SIZE); | ^~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:67:19: note: expanded from macro 'min' 67 | #define min(x, y) __careful_cmp(x, y, <) | ^~~~~~~~~~~~~~~~~~~~~~ include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp' 36 | __builtin_choose_expr(__safe_cmp(x, y), \ | ^~~~~~~~~~~~~~~~ include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp' 26 | (__typecheck(x, y) && __no_side_effects(x, y)) | ^~~~~~~~~~~~~~~~~ include/linux/minmax.h:20:28: note: expanded from macro '__typecheck' 20 | (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1))) | ~~~~~~~~~~~~~~ ^ ~~~~~~~~~~~~~~ 8 warnings generated. vim +525 include/linux/highmem.h 509 510 /** 511 * memcpy_to_folio - Copy a range of bytes to a folio 512 * @folio: The folio to write to. 513 * @offset: The first byte in the folio to store to. 514 * @from: The memory to copy from. 515 * @len: The number of bytes to copy. 516 */ 517 static inline void memcpy_to_folio(struct folio *folio, size_t offset, 518 const char *from, size_t len) 519 { 520 size_t n = len; 521 522 VM_BUG_ON(offset + len > folio_size(folio)); 523 524 if (folio_test_highmem(folio)) > 525 n = min(len, PAGE_SIZE - offset_in_page(offset)); 526 for (;;) { 527 char *to = kmap_local_folio(folio, offset); 528 memcpy(to, from, n); 529 kunmap_local(to); 530 if (!folio_test_highmem(folio) || n == len) 531 break; 532 offset += n; 533 len -= n; > 534 n = min(len, PAGE_SIZE); 535 } 536 flush_dcache_folio(folio); 537 } 538 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki