[kbuild-all] [djwong-xfs:repair-xattrs 44/141] fs/xfs/xfs_dquot.c:262:2: warning: variable 'blftype' is used uninitialized whenever switch default is taken

tree: https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git repair-xattrs head: 3e70ca2b22ea70af0d1579536c4377530abcc8ee commit: 78e538ffa882a05793dd6d8a0a10a01e2136023c [44/141] xfs: split the incore dquot type into a separate field config: arm64-randconfig-r032-20200714 (attached as .config) compiler: clang version 11.0.0 (https://github.com/llvm/llvm-project 02946de3802d3bc65bc9f2eb9b8d4969b5a7add8) 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 # install arm64 cross compiling tool for clang build # apt-get install binutils-aarch64-linux-gnu git checkout 78e538ffa882a05793dd6d8a0a10a01e2136023c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): default: ^~~~~~~ fs/xfs/xfs_dquot.c:267:30: note: uninitialized use occurs here xfs_trans_dquot_buf(tp, bp, blftype); ^~~~~~~ fs/xfs/xfs_dquot.c:224:23: note: initialize the variable 'blftype' to silence this warning unsigned int blftype; ^ = 0 default: ^~~~~~~ fs/xfs/xfs_dquot.c:285:23: note: uninitialized use occurs here if (!(mp->m_qflags & qflag)) ^~~~~ fs/xfs/xfs_dquot.c:223:21: note: initialize the variable 'qflag' to silence this warning unsigned int qflag; ^ = 0 2 warnings generated. vim +/blftype +262 fs/xfs/xfs_dquot.c 208 209 /* 210 * initialize a buffer full of dquots and log the whole thing 211 */ 212 STATIC void 213 xfs_qm_init_dquot_blk( 214 struct xfs_trans *tp, 215 struct xfs_mount *mp, 216 xfs_dqid_t id, 217 xfs_dqtype_t type, 218 struct xfs_buf *bp) 219 { 220 struct xfs_quotainfo *q = mp->m_quotainfo; 221 struct xfs_dqblk *d; 222 xfs_dqid_t curid; 223 unsigned int qflag; 224 unsigned int blftype; 225 int i; 226 227 ASSERT(tp); 228 ASSERT(xfs_buf_islocked(bp)); 229 230 d = bp->b_addr; 231 232 /* 233 * ID of the first dquot in the block - id's are zero based. 234 */ 235 curid = id - (id % q->qi_dqperchunk); 236 memset(d, 0, BBTOB(q->qi_dqchunklen)); 237 for (i = 0; i < q->qi_dqperchunk; i++, d++, curid++) { 238 d->dd_diskdq.d_magic = cpu_to_be16(XFS_DQUOT_MAGIC); 239 d->dd_diskdq.d_version = XFS_DQUOT_VERSION; 240 d->dd_diskdq.d_id = cpu_to_be32(curid); 241 d->dd_diskdq.d_flags = xfs_dquot_type_to_disk(type); 242 if (xfs_sb_version_hascrc(&mp->m_sb)) { 243 uuid_copy(&d->dd_uuid, &mp->m_sb.sb_meta_uuid); 244 xfs_update_cksum((char *)d, sizeof(struct xfs_dqblk), 245 XFS_DQUOT_CRC_OFF); 246 } 247 } 248 249 switch (type) { 250 case XFS_DQTYPE_USER: 251 qflag = XFS_UQUOTA_CHKD; 252 blftype = XFS_BLF_UDQUOT_BUF; 253 break; 254 case XFS_DQTYPE_PROJ: 255 qflag = XFS_PQUOTA_CHKD; 256 blftype = XFS_BLF_PDQUOT_BUF; 257 break; 258 case XFS_DQTYPE_GROUP: 259 qflag = XFS_GQUOTA_CHKD; 260 blftype = XFS_BLF_GDQUOT_BUF; 261 break; 263 ASSERT(0); 264 break; 265 } 266 267 xfs_trans_dquot_buf(tp, bp, blftype); 268 269 /* 270 * quotacheck uses delayed writes to update all the dquots on disk in an 271 * efficient manner instead of logging the individual dquot changes as 272 * they are made. However if we log the buffer allocated here and crash 273 * after quotacheck while the logged initialisation is still in the 274 * active region of the log, log recovery can replay the dquot buffer 275 * initialisation over the top of the checked dquots and corrupt quota 276 * accounting. 277 * 278 * To avoid this problem, quotacheck cannot log the initialised buffer. 279 * We must still dirty the buffer and write it back before the 280 * allocation transaction clears the log. Therefore, mark the buffer as 281 * ordered instead of logging it directly. This is safe for quotacheck 282 * because it detects and repairs allocated but initialized dquot blocks 283 * in the quota inodes. 284 */ 285 if (!(mp->m_qflags & qflag)) 286 xfs_trans_ordered_buf(tp, bp); 287 else 288 xfs_trans_log_buf(tp, bp, 0, BBTOB(q->qi_dqchunklen) - 1); 289 } 290 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org