tree: https://github.com/ammarfaizi2/linux-block dhowells/linux-fs/netfs-lib head: 41c3c11032cdbee08d6be046b0caa2776b4fd437 commit: 5dcff5ed720e69e0ffec5ade8d8a0df96d0b0369 [20/30] netfs: Add a netfs inode context config: i386-randconfig-a015 (https://download.01.org/0day-ci/archive/20220121/202201212250.cPTkICQp-lk...) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 7b3d30728816403d1fd73cc5082e9fb761262bce) 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/ammarfaizi2/linux-block/commit/5dcff5ed720e69e0ffec5ad... git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block git fetch --no-tags ammarfaizi2-block dhowells/linux-fs/netfs-lib git checkout 5dcff5ed720e69e0ffec5ade8d8a0df96d0b0369 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash fs/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): fs/netfs/read_helper.c:979:14: warning: variable 'folio' is uninitialized when used here [-Wuninitialized] folio_put(folio); ^~~~~ fs/netfs/read_helper.c:928:21: note: initialize the variable 'folio' to silence this warning struct folio *folio; ^ = NULL if (!netfs_is_cache_enabled(ctx) && ^ 1 warning and 1 error generated. vim +/netfs_is_cache_enabled +1256 fs/netfs/read_helper.c 1183 1184 /** 1185 * netfs_write_begin - Helper to prepare for writing 1186 * @file: The file to read from 1187 * @mapping: The mapping to read from 1188 * @pos: File position at which the write will begin 1189 * @len: The length of the write (may extend beyond the end of the folio chosen) 1190 * @aop_flags: AOP_* flags 1191 * @_folio: Where to put the resultant folio 1192 * @_fsdata: Place for the netfs to store a cookie 1193 * 1194 * Pre-read data for a write-begin request by drawing data from the cache if 1195 * possible, or the netfs if not. Space beyond the EOF is zero-filled. 1196 * Multiple I/O requests from different sources will get munged together. If 1197 * necessary, the readahead window can be expanded in either direction to a 1198 * more convenient alighment for RPC efficiency or to make storage in the cache 1199 * feasible. 1200 * 1201 * The calling netfs must provide a table of operations, only one of which, 1202 * issue_op, is mandatory. 1203 * 1204 * The check_write_begin() operation can be provided to check for and flush 1205 * conflicting writes once the folio is grabbed and locked. It is passed a 1206 * pointer to the fsdata cookie that gets returned to the VM to be passed to 1207 * write_end. It is permitted to sleep. It should return 0 if the request 1208 * should go ahead; unlock the folio and return -EAGAIN to cause the folio to 1209 * be regot; or return an error. 1210 * 1211 * The calling netfs must initialise a netfs context contiguous to the vfs 1212 * inode before calling this. 1213 * 1214 * This is usable whether or not caching is enabled. 1215 */ 1216 int netfs_write_begin(struct file *file, struct address_space *mapping, 1217 loff_t pos, unsigned int len, unsigned int aop_flags, 1218 struct folio **_folio, void **_fsdata) 1219 { 1220 struct netfs_read_request *rreq; 1221 struct netfs_i_context *ctx = netfs_i_context(file_inode(file )); 1222 struct folio *folio; 1223 unsigned int debug_index = 0, fgp_flags; 1224 pgoff_t index = pos >> PAGE_SHIFT; 1225 int ret; 1226 1227 DEFINE_READAHEAD(ractl, file, NULL, mapping, index); 1228 1229 retry: 1230 fgp_flags = FGP_LOCK | FGP_WRITE | FGP_CREAT | FGP_STABLE; 1231 if (aop_flags & AOP_FLAG_NOFS) 1232 fgp_flags |= FGP_NOFS; 1233 folio = __filemap_get_folio(mapping, index, fgp_flags, 1234 mapping_gfp_mask(mapping)); 1235 if (!folio) 1236 return -ENOMEM; 1237 1238 if (ctx->ops->check_write_begin) { 1239 /* Allow the netfs (eg. ceph) to flush conflicts. */ 1240 ret = ctx->ops->check_write_begin(file, pos, len, folio, _fsdata); 1241 if (ret < 0) { 1242 trace_netfs_failure(NULL, NULL, ret, netfs_fail_check_write_begin); 1243 if (ret == -EAGAIN) 1244 goto retry; 1245 goto error; 1246 } 1247 } 1248 1249 if (folio_test_uptodate(folio)) 1250 goto have_folio; 1251 1252 /* If the folio is beyond the EOF, we want to clear it - unless it's 1253 * within the cache granule containing the EOF, in which case we need 1254 * to preload the granule. 1255 */ --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org