tree: https://git.kernel.org/pub/scm/linux/kernel/git/djwong/xfs-linux.git refactor-log-recovery head: 2dcdc305cfc2b8b1beee483cf8ae5c674d9fac86 commit: 06450afc33740b8a0d2d62b483595f9c11c0fb8b [299/314] xfs: refactor log recovery item dispatch for pass1 commit functions If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; smatch warnings: fs/xfs/xfs_buf_item.c:1372 xlog_recover_buffer_pass1() error: potential null dereference 'bcp'. (kmem_alloc returns null) vim +/bcp +1372 fs/xfs/xfs_buf_item.c 1321 1322 /* 1323 * Build up the table of buf cancel records so that we don't replay 1324 * cancelled data in the second pass. For buffer records that are 1325 * not cancel records, there is nothing to do here so we just return. 1326 * 1327 * If we get a cancel record which is already in the table, this indicates 1328 * that the buffer was cancelled multiple times. In order to ensure 1329 * that during pass 2 we keep the record in the table until we reach its 1330 * last occurrence in the log, we keep a reference count in the cancel 1331 * record in the table to tell us how many times we expect to see this 1332 * record during the second pass. 1333 */ 1334 STATIC int 1335 xlog_recover_buffer_pass1( 1336 struct xlog *log, 1337 struct xlog_recover_item *item) 1338 { 1339 xfs_buf_log_format_t *buf_f = item->ri_buf[0].i_addr; 1340 struct list_head *bucket; 1341 struct xfs_buf_cancel *bcp; 1342 1343 if (!xfs_buf_log_check_iovec(&item->ri_buf[0])) { 1344 xfs_err(log->l_mp, "bad buffer log item size (%d)", 1345 item->ri_buf[0].i_len); 1346 return -EFSCORRUPTED; 1347 } 1348 1349 /* 1350 * If this isn't a cancel buffer item, then just return. 1351 */ 1352 if (!(buf_f->blf_flags & XFS_BLF_CANCEL)) { 1353 trace_xfs_log_recover_buf_not_cancel(log, buf_f); 1354 return 0; 1355 } 1356 1357 /* 1358 * Insert an xfs_buf_cancel record into the hash table of them. 1359 * If there is already an identical record, bump its reference count. 1360 */ 1361 bucket = XLOG_BUF_CANCEL_BUCKET(log, buf_f->blf_blkno); 1362 list_for_each_entry(bcp, bucket, bc_list) { 1363 if (bcp->bc_blkno == buf_f->blf_blkno && 1364 bcp->bc_len == buf_f->blf_len) { 1365 bcp->bc_refcount++; 1366 trace_xfs_log_recover_buf_cancel_ref_inc(log, buf_f); 1367 return 0; 1368 } 1369 } 1370 1371 bcp = kmem_alloc(sizeof(struct xfs_buf_cancel), 0); 1373 bcp->bc_len = buf_f->blf_len; 1374 bcp->bc_refcount = 1; 1375 list_add_tail(&bcp->bc_list, bucket); 1376 1377 trace_xfs_log_recover_buf_cancel_add(log, buf_f); 1378 return 0; 1379 } 1380 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org