Hi, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on soc/for-next] [also build test WARNING on linus/master linux/master v5.18-rc1 next-20220404] [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/intel-lab-lkp/linux/commits/guoren-kernel-org/csky-Add-C-based-string-functions/20220404-222518 base: https://git.kernel.org/pub/scm/linux/kernel/git/soc/soc.git for-next config: csky-defconfig (https://download.01.org/0day-ci/archive/20220405/202204051450.UN2k1raL-lkp@xxxxxxxxx/config) compiler: csky-linux-gcc (GCC) 11.2.0 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 # https://github.com/intel-lab-lkp/linux/commit/e8231df5e8121c094f8668e0c850381873aa4249 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review guoren-kernel-org/csky-Add-C-based-string-functions/20220404-222518 git checkout e8231df5e8121c094f8668e0c850381873aa4249 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross O=build_dir ARCH=csky SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> arch/csky/lib/string.c:30:7: warning: no previous prototype for '__memcpy' [-Wmissing-prototypes] 30 | void *__memcpy(void *dest, const void *src, size_t count) | ^~~~~~~~ >> arch/csky/lib/string.c:94:7: warning: no previous prototype for '__memmove' [-Wmissing-prototypes] 94 | void *__memmove(void *dest, const void *src, size_t count) | ^~~~~~~~~ >> arch/csky/lib/string.c:113:7: warning: no previous prototype for '__memset' [-Wmissing-prototypes] 113 | void *__memset(void *s, int c, size_t count) | ^~~~~~~~ vim +/__memcpy +30 arch/csky/lib/string.c 29 > 30 void *__memcpy(void *dest, const void *src, size_t count) 31 { 32 union const_types s = { .as_u8 = src }; 33 union types d = { .as_u8 = dest }; 34 int distance = 0; 35 36 if (count < MIN_THRESHOLD) 37 goto copy_remainder; 38 39 /* Copy a byte at time until destination is aligned. */ 40 for (; d.as_uptr & WORD_MASK; count--) 41 *d.as_u8++ = *s.as_u8++; 42 43 distance = s.as_uptr & WORD_MASK; 44 45 if (distance) { 46 unsigned long last, next; 47 48 /* 49 * s is distance bytes ahead of d, and d just reached 50 * the alignment boundary. Move s backward to word align it 51 * and shift data to compensate for distance, in order to do 52 * word-by-word copy. 53 */ 54 s.as_u8 -= distance; 55 56 next = s.as_ulong[0]; 57 for (; count >= BYTES_LONG; count -= BYTES_LONG) { 58 last = next; 59 next = s.as_ulong[1]; 60 61 d.as_ulong[0] = last >> (distance * 8) | 62 next << ((BYTES_LONG - distance) * 8); 63 64 d.as_ulong++; 65 s.as_ulong++; 66 } 67 68 /* Restore s with the original offset. */ 69 s.as_u8 += distance; 70 } else { 71 /* 72 * If the source and dest lower bits are the same, do a simple 73 * 32/64 bit wide copy. 74 */ 75 for (; count >= BYTES_LONG; count -= BYTES_LONG) 76 *d.as_ulong++ = *s.as_ulong++; 77 } 78 79 copy_remainder: 80 while (count--) 81 *d.as_u8++ = *s.as_u8++; 82 83 return dest; 84 } 85 EXPORT_SYMBOL(__memcpy); 86 87 void *memcpy(void *dest, const void *src, size_t count) __weak __alias(__memcpy); 88 EXPORT_SYMBOL(memcpy); 89 90 /* 91 * Simply check if the buffer overlaps an call memcpy() in case, 92 * otherwise do a simple one byte at time backward copy. 93 */ > 94 void *__memmove(void *dest, const void *src, size_t count) 95 { 96 if (dest < src || src + count <= dest) 97 return memcpy(dest, src, count); 98 99 if (dest > src) { 100 const char *s = src + count; 101 char *tmp = dest + count; 102 103 while (count--) 104 *--tmp = *--s; 105 } 106 return dest; 107 } 108 EXPORT_SYMBOL(__memmove); 109 110 void *memmove(void *dest, const void *src, size_t count) __weak __alias(__memmove); 111 EXPORT_SYMBOL(memmove); 112 > 113 void *__memset(void *s, int c, size_t count) 114 { 115 union types dest = { .as_u8 = s }; 116 117 if (count >= MIN_THRESHOLD) { 118 unsigned long cu = (unsigned long)c; 119 120 /* Compose an ulong with 'c' repeated 4/8 times */ 121 cu |= cu << 8; 122 cu |= cu << 16; 123 /* Suppress warning on 32 bit machines */ 124 cu |= (cu << 16) << 16; 125 126 for (; count && dest.as_uptr & WORD_MASK; count--) 127 *dest.as_u8++ = c; 128 129 /* Copy using the largest size allowed */ 130 for (; count >= BYTES_LONG; count -= BYTES_LONG) 131 *dest.as_ulong++ = cu; 132 } 133 134 /* copy the remainder */ 135 while (count--) 136 *dest.as_u8++ = c; 137 138 return s; 139 } 140 EXPORT_SYMBOL(__memset); 141 -- 0-DAY CI Kernel Test Service https://01.org/lkp
