[kbuild-all] drivers/w1/slaves/w1_ds28e04.c:360 crccheck_store() warn: assigning (-48) to unsigned variable 'val'

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 4b6c093e21d36bede0fd88fd0aeb3b03647260e4 commit: 80591e61a0f7e88deaada69844e4a31280c4a38f kbuild: tell sparse about the $ARCH date: 9 months ago config: s390-randconfig-m031-20200816 (attached as .config) compiler: s390-linux-gcc (GCC) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; New smatch warnings: drivers/w1/slaves/w1_ds28e04.c:360 crccheck_store() warn: assigning (-48) to unsigned variable 'val' Old smatch warnings: arch/s390/include/asm/uaccess.h:113 __put_user_fn() error: uninitialized symbol 'rc'. arch/s390/include/asm/uaccess.h:143 __get_user_fn() error: uninitialized symbol 'rc'. vim +/val +360 drivers/w1/slaves/w1_ds28e04.c fbf7f7b4e2ae40 Markus Franke 2012-05-26 347 fa33a65a9cf7e2 Greg Kroah-Hartman 2013-08-21 348 static ssize_t crccheck_store(struct device *dev, struct device_attribute *attr, fbf7f7b4e2ae40 Markus Franke 2012-05-26 349 const char *buf, size_t count) fbf7f7b4e2ae40 Markus Franke 2012-05-26 350 { fbf7f7b4e2ae40 Markus Franke 2012-05-26 351 char val; fbf7f7b4e2ae40 Markus Franke 2012-05-26 352 fbf7f7b4e2ae40 Markus Franke 2012-05-26 353 if (count != 1 || !buf) fbf7f7b4e2ae40 Markus Franke 2012-05-26 354 return -EINVAL; fbf7f7b4e2ae40 Markus Franke 2012-05-26 355 fbf7f7b4e2ae40 Markus Franke 2012-05-26 356 if (get_user(val, buf)) fbf7f7b4e2ae40 Markus Franke 2012-05-26 357 return -EFAULT; fbf7f7b4e2ae40 Markus Franke 2012-05-26 358 fbf7f7b4e2ae40 Markus Franke 2012-05-26 359 /* convert to decimal */ fbf7f7b4e2ae40 Markus Franke 2012-05-26 @360 val = val - 0x30; fbf7f7b4e2ae40 Markus Franke 2012-05-26 361 if (val != 0 && val != 1) fbf7f7b4e2ae40 Markus Franke 2012-05-26 362 return -EINVAL; fbf7f7b4e2ae40 Markus Franke 2012-05-26 363 fbf7f7b4e2ae40 Markus Franke 2012-05-26 364 /* set the new value */ fbf7f7b4e2ae40 Markus Franke 2012-05-26 365 w1_enable_crccheck = val; fbf7f7b4e2ae40 Markus Franke 2012-05-26 366 fbf7f7b4e2ae40 Markus Franke 2012-05-26 367 return sizeof(w1_enable_crccheck); fbf7f7b4e2ae40 Markus Franke 2012-05-26 368 } fbf7f7b4e2ae40 Markus Franke 2012-05-26 369 :::::: The code at line 360 was first introduced by commit :::::: fbf7f7b4e2ae40f790828c86d31beff2d49e9ac8 w1: Add 1-wire slave device driver for DS28E04-100 :::::: TO: Markus Franke <franm(a)hrz.tu-chemnitz.de&gt; :::::: CC: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org