[dlemoal-libata:for-5.17-logging 28/79] drivers/ata/sata_mv.c:1276:30: warning: 'dw' is used uninitialized

[kernel test robot]

tree:   git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata.git for-5.17-logging
head:   7830f5151b3b153a04daec48653458c9a2db7b16
commit: 8e1aff057cd5a2d00d19754fabf7095ba54a7e91 [28/79] sata_mv: replace DPRINTK with dynamic debugging
config: sparc64-randconfig-r005-20211230 (https://download.01.org/0day-ci/archive/20211231/202112311057.WDs1psTQ-lkp@xxxxxxxxx/config)
compiler: sparc64-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://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata.git/commit/?id=8e1aff057cd5a2d00d19754fabf7095ba54a7e91
        git remote add dlemoal-libata git://git.kernel.org/pub/scm/linux/kernel/git/dlemoal/libata.git
        git fetch --no-tags dlemoal-libata for-5.17-logging
        git checkout 8e1aff057cd5a2d00d19754fabf7095ba54a7e91
        # 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=sparc64 SHELL=/bin/bash drivers/ata/

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

   drivers/ata/sata_mv.c: In function 'mv_pci_error':
>> drivers/ata/sata_mv.c:1276:30: warning: 'dw' is used uninitialized [-Wuninitialized]
    1276 |                         o += snprintf(linebuf + o, 38 - o,
         |                              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    1277 |                                       "%08x ", dw);
         |                                       ~~~~~~~~~~~~
   drivers/ata/sata_mv.c:1270:13: note: 'dw' was declared here
    1270 |         u32 dw;
         |             ^~


vim +/dw +1276 drivers/ata/sata_mv.c

  1266	
  1267	static void mv_dump_pci_cfg(struct pci_dev *pdev, unsigned bytes)
  1268	{
  1269		int b, w, o;
  1270		u32 dw;
  1271		unsigned char linebuf[38];
  1272	
  1273		for (b = 0; b < bytes; ) {
  1274			for (w = 0, o = 0; b < bytes && w < 4; w++) {
  1275				(void) pci_read_config_dword(pdev, b, &dw);
> 1276				o += snprintf(linebuf + o, 38 - o,
  1277					      "%08x ", dw);
  1278				b += sizeof(u32);
  1279			}
  1280			dev_dbg(&pdev->dev, "%s: %02x: %s\n",
  1281				__func__, b, linebuf);
  1282		}
  1283	}
  1284	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx