Hi Michael, url: https://github.com/0day-ci/linux/commits/Michael-Tretter/Add-ZynqMP-VCU-Allegro-DVT-H-264-encoder-driver/20190504-161958 base: git://linuxtv.org/media_tree.git master If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> smatch warnings: drivers/media/platform/allegro-dvt/nal-h264.c:205 rbsp_read_bit() warn: signedness bug returning '(-22)' drivers/media/platform/allegro-dvt/nal-h264.c:259 rbsp_read_bits() warn: unsigned 'bit' is never less than zero. # https://github.com/0day-ci/linux/commit/eba69588199f08008a1fb4ad24e1f3e66d0080e3 git remote add linux-review https://github.com/0day-ci/linux git remote update linux-review git checkout eba69588199f08008a1fb4ad24e1f3e66d0080e3 vim +205 drivers/media/platform/allegro-dvt/nal-h264.c eba69588 Michael Tretter 2019-05-03 188 eba69588 Michael Tretter 2019-05-03 189 static inline bool rbsp_read_bit(struct rbsp *rbsp) ^^^^ eba69588 Michael Tretter 2019-05-03 190 { eba69588 Michael Tretter 2019-05-03 191 int shift; eba69588 Michael Tretter 2019-05-03 192 int ofs; eba69588 Michael Tretter 2019-05-03 193 bool bit; eba69588 Michael Tretter 2019-05-03 194 int err; eba69588 Michael Tretter 2019-05-03 195 eba69588 Michael Tretter 2019-05-03 196 if (rbsp->num_consecutive_zeros == 22) { eba69588 Michael Tretter 2019-05-03 197 err = discard_emulation_prevention_three_byte(rbsp); eba69588 Michael Tretter 2019-05-03 198 if (err) eba69588 Michael Tretter 2019-05-03 199 return err; ^^^^^^^^^^ eba69588 Michael Tretter 2019-05-03 200 } eba69588 Michael Tretter 2019-05-03 201 eba69588 Michael Tretter 2019-05-03 202 shift = 7 - (rbsp->pos % 8); eba69588 Michael Tretter 2019-05-03 203 ofs = rbsp->pos / 8; eba69588 Michael Tretter 2019-05-03 204 if (ofs >= rbsp->size) eba69588 Michael Tretter 2019-05-03 @205 return -EINVAL; ^^^^^^^^^^^^^^ Probably this function should return int instead of bool. eba69588 Michael Tretter 2019-05-03 206 eba69588 Michael Tretter 2019-05-03 207 bit = (rbsp->data[ofs] >> shift) & 1; eba69588 Michael Tretter 2019-05-03 208 eba69588 Michael Tretter 2019-05-03 209 rbsp->pos++; eba69588 Michael Tretter 2019-05-03 210 eba69588 Michael Tretter 2019-05-03 211 if (bit == 1 || eba69588 Michael Tretter 2019-05-03 212 (rbsp->num_consecutive_zeros < 7 && (rbsp->pos % 8 == 0))) eba69588 Michael Tretter 2019-05-03 213 rbsp->num_consecutive_zeros = 0; eba69588 Michael Tretter 2019-05-03 214 else eba69588 Michael Tretter 2019-05-03 215 rbsp->num_consecutive_zeros++; eba69588 Michael Tretter 2019-05-03 216 eba69588 Michael Tretter 2019-05-03 217 return bit; eba69588 Michael Tretter 2019-05-03 218 } [ snip ] eba69588 Michael Tretter 2019-05-03 248 static inline int rbsp_read_bits(struct rbsp *rbsp, int n, unsigned int *value) eba69588 Michael Tretter 2019-05-03 249 { eba69588 Michael Tretter 2019-05-03 250 int i; eba69588 Michael Tretter 2019-05-03 251 unsigned int bit; ^^^^^^^^^^^^^^^^ eba69588 Michael Tretter 2019-05-03 252 unsigned int tmp = 0; eba69588 Michael Tretter 2019-05-03 253 eba69588 Michael Tretter 2019-05-03 254 if (n > 8 * sizeof(*value)) eba69588 Michael Tretter 2019-05-03 255 return -EINVAL; eba69588 Michael Tretter 2019-05-03 256 eba69588 Michael Tretter 2019-05-03 257 for (i = n; i > 0; i--) { eba69588 Michael Tretter 2019-05-03 258 bit = rbsp_read_bit(rbsp); eba69588 Michael Tretter 2019-05-03 @259 if (bit < 0) ^^^^^^^ eba69588 Michael Tretter 2019-05-03 260 return bit; eba69588 Michael Tretter 2019-05-03 261 tmp |= bit << (i - 1); eba69588 Michael Tretter 2019-05-03 262 } eba69588 Michael Tretter 2019-05-03 263 eba69588 Michael Tretter 2019-05-03 264 if (value) eba69588 Michael Tretter 2019-05-03 265 *value = tmp; eba69588 Michael Tretter 2019-05-03 266 eba69588 Michael Tretter 2019-05-03 267 return 0; eba69588 Michael Tretter 2019-05-03 268 } eba69588 Michael Tretter 2019-05-03 269 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation