Hi Joanne, kernel test robot noticed the following build warnings: https://git-scm.com/docs/git-format-patch#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Joanne-Koong/fuse-support-copying-large-folios/20250426-081219 base: https://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse.git for-next patch link: https://lore.kernel.org/r/20250426000828.3216220-4-joannelkoong%40gmail.com patch subject: [PATCH v5 03/11] fuse: refactor fuse_fill_write_pages() config: i386-randconfig-141-20250426 (https://download.01.org/0day-ci/archive/20250427/202504270319.GmkEM1Xg-lkp@xxxxxxxxx/config) compiler: gcc-12 (Debian 12.2.0-14) 12.2.0 If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> | Closes: https://lore.kernel.org/r/202504270319.GmkEM1Xg-lkp@xxxxxxxxx/ smatch warnings: fs/fuse/file.c:1207 fuse_fill_write_pages() error: uninitialized symbol 'err'. vim +/err +1207 fs/fuse/file.c 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1127 static ssize_t fuse_fill_write_pages(struct fuse_io_args *ia, ea9b9907b82a09 Nicholas Piggin 2008-04-30 1128 struct address_space *mapping, 338f2e3f3341a9 Miklos Szeredi 2019-09-10 1129 struct iov_iter *ii, loff_t pos, 338f2e3f3341a9 Miklos Szeredi 2019-09-10 1130 unsigned int max_pages) ea9b9907b82a09 Nicholas Piggin 2008-04-30 1131 { 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1132 struct fuse_args_pages *ap = &ia->ap; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1133 struct fuse_conn *fc = get_fuse_conn(mapping->host); 09cbfeaf1a5a67 Kirill A. Shutemov 2016-04-01 1134 unsigned offset = pos & (PAGE_SIZE - 1); ea9b9907b82a09 Nicholas Piggin 2008-04-30 1135 size_t count = 0; dfda790dfda452 Joanne Koong 2025-04-25 1136 unsigned int num; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1137 int err; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1138 dfda790dfda452 Joanne Koong 2025-04-25 1139 num = min(iov_iter_count(ii), fc->max_write); Can iov_iter_count() return zero here? dfda790dfda452 Joanne Koong 2025-04-25 1140 num = min(num, max_pages << PAGE_SHIFT); dfda790dfda452 Joanne Koong 2025-04-25 1141 338f2e3f3341a9 Miklos Szeredi 2019-09-10 1142 ap->args.in_pages = true; 68bfb7eb7f7de3 Joanne Koong 2024-10-24 1143 ap->descs[0].offset = offset; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1144 dfda790dfda452 Joanne Koong 2025-04-25 1145 while (num) { ea9b9907b82a09 Nicholas Piggin 2008-04-30 1146 size_t tmp; 9bafbe7ae01321 Josef Bacik 2024-09-30 1147 struct folio *folio; 09cbfeaf1a5a67 Kirill A. Shutemov 2016-04-01 1148 pgoff_t index = pos >> PAGE_SHIFT; dfda790dfda452 Joanne Koong 2025-04-25 1149 unsigned bytes = min(PAGE_SIZE - offset, num); ea9b9907b82a09 Nicholas Piggin 2008-04-30 1150 ea9b9907b82a09 Nicholas Piggin 2008-04-30 1151 again: 9bafbe7ae01321 Josef Bacik 2024-09-30 1152 folio = __filemap_get_folio(mapping, index, FGP_WRITEBEGIN, 9bafbe7ae01321 Josef Bacik 2024-09-30 1153 mapping_gfp_mask(mapping)); 9bafbe7ae01321 Josef Bacik 2024-09-30 1154 if (IS_ERR(folio)) { 9bafbe7ae01321 Josef Bacik 2024-09-30 1155 err = PTR_ERR(folio); ea9b9907b82a09 Nicholas Piggin 2008-04-30 1156 break; 9bafbe7ae01321 Josef Bacik 2024-09-30 1157 } ea9b9907b82a09 Nicholas Piggin 2008-04-30 1158 931e80e4b3263d anfei zhou 2010-02-02 1159 if (mapping_writably_mapped(mapping)) 9bafbe7ae01321 Josef Bacik 2024-09-30 1160 flush_dcache_folio(folio); 931e80e4b3263d anfei zhou 2010-02-02 1161 9bafbe7ae01321 Josef Bacik 2024-09-30 1162 tmp = copy_folio_from_iter_atomic(folio, offset, bytes, ii); 9bafbe7ae01321 Josef Bacik 2024-09-30 1163 flush_dcache_folio(folio); ea9b9907b82a09 Nicholas Piggin 2008-04-30 1164 ea9b9907b82a09 Nicholas Piggin 2008-04-30 1165 if (!tmp) { 9bafbe7ae01321 Josef Bacik 2024-09-30 1166 folio_unlock(folio); 9bafbe7ae01321 Josef Bacik 2024-09-30 1167 folio_put(folio); faa794dd2e17e7 Dave Hansen 2025-01-29 1168 faa794dd2e17e7 Dave Hansen 2025-01-29 1169 /* faa794dd2e17e7 Dave Hansen 2025-01-29 1170 * Ensure forward progress by faulting in faa794dd2e17e7 Dave Hansen 2025-01-29 1171 * while not holding the folio lock: faa794dd2e17e7 Dave Hansen 2025-01-29 1172 */ faa794dd2e17e7 Dave Hansen 2025-01-29 1173 if (fault_in_iov_iter_readable(ii, bytes)) { faa794dd2e17e7 Dave Hansen 2025-01-29 1174 err = -EFAULT; faa794dd2e17e7 Dave Hansen 2025-01-29 1175 break; faa794dd2e17e7 Dave Hansen 2025-01-29 1176 } faa794dd2e17e7 Dave Hansen 2025-01-29 1177 ea9b9907b82a09 Nicholas Piggin 2008-04-30 1178 goto again; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1179 } ea9b9907b82a09 Nicholas Piggin 2008-04-30 1180 ea9b9907b82a09 Nicholas Piggin 2008-04-30 1181 err = 0; f2ef459bab7326 Joanne Koong 2024-10-24 1182 ap->folios[ap->num_folios] = folio; 68bfb7eb7f7de3 Joanne Koong 2024-10-24 1183 ap->descs[ap->num_folios].length = tmp; f2ef459bab7326 Joanne Koong 2024-10-24 1184 ap->num_folios++; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1185 ea9b9907b82a09 Nicholas Piggin 2008-04-30 1186 count += tmp; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1187 pos += tmp; dfda790dfda452 Joanne Koong 2025-04-25 1188 num -= tmp; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1189 offset += tmp; 09cbfeaf1a5a67 Kirill A. Shutemov 2016-04-01 1190 if (offset == PAGE_SIZE) ea9b9907b82a09 Nicholas Piggin 2008-04-30 1191 offset = 0; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1192 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1193 /* If we copied full page, mark it uptodate */ 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1194 if (tmp == PAGE_SIZE) 9bafbe7ae01321 Josef Bacik 2024-09-30 1195 folio_mark_uptodate(folio); 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1196 9bafbe7ae01321 Josef Bacik 2024-09-30 1197 if (folio_test_uptodate(folio)) { 9bafbe7ae01321 Josef Bacik 2024-09-30 1198 folio_unlock(folio); 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1199 } else { f2ef459bab7326 Joanne Koong 2024-10-24 1200 ia->write.folio_locked = true; 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1201 break; 4f06dd92b5d0a6 Vivek Goyal 2020-10-21 1202 } dfda790dfda452 Joanne Koong 2025-04-25 1203 if (!fc->big_writes || offset != 0) 78bb6cb9a890d3 Miklos Szeredi 2008-05-12 1204 break; dfda790dfda452 Joanne Koong 2025-04-25 1205 } ea9b9907b82a09 Nicholas Piggin 2008-04-30 1206 ea9b9907b82a09 Nicholas Piggin 2008-04-30 @1207 return count > 0 ? count : err; ea9b9907b82a09 Nicholas Piggin 2008-04-30 1208 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
