Hi Daniel, First bad commit (maybe != root cause): tree: https://chromium.googlesource.com/chromiumos/third_party/kernel chromeos-5.15 head: b4852fbf90916fdc2f1e0e282e100f7e0e889d77 commit: e5b3b81d1d68b255b8315890a22dcf5d9cf488c6 [1676/2818] CHROMIUM: drivers: Create pkglist for configuration config: arm-chromiumos-arm-customedconfig-chrome-os:chromeos-5.15:b4852fbf90916fdc2f1e0e282e100f7e0e889d77 (https://download.01.org/0day-ci/archive/20211212/202112121251.RqHvXrTR-lk...) compiler: arm-linux-gnueabi-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 git remote add chrome-os https://chromium.googlesource.com/chromiumos/third_party/kernel git fetch --no-tags chrome-os chromeos-5.15 git checkout e5b3b81d1d68b255b8315890a22dcf5d9cf488c6 # 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=arm SHELL=/bin/bash 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 >>): 382 | esdfs_read_iter(struct kiocb *iocb, struct iov_iter *iter) | ^~~~~~~~~~~~~~~ 410 | esdfs_write_iter(struct kiocb *iocb, struct iov_iter *iter) | ^~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors -- fs/esdfs/derive.c: In function 'esdfs_derive_perms': 76 | int ret; | ^~~ cc1: all warnings being treated as errors vim +/esdfs_read_iter +382 fs/esdfs/file.c 1704af1484c6d2 Russ W. Knize 2013-04-07 377 1704af1484c6d2 Russ W. Knize 2013-04-07 378 /* 1704af1484c6d2 Russ W. Knize 2013-04-07 379 * Wrapfs read_iter, redirect modified iocb to lower read_iter 1704af1484c6d2 Russ W. Knize 2013-04-07 380 */ 1704af1484c6d2 Russ W. Knize 2013-04-07 381 ssize_t 1704af1484c6d2 Russ W. Knize 2013-04-07 @382 esdfs_read_iter(struct kiocb *iocb, struct iov_iter *iter) 1704af1484c6d2 Russ W. Knize 2013-04-07 383 { 1704af1484c6d2 Russ W. Knize 2013-04-07 384 int err; 1704af1484c6d2 Russ W. Knize 2013-04-07 385 struct file *file = iocb->ki_filp, *lower_file; 1704af1484c6d2 Russ W. Knize 2013-04-07 386 1704af1484c6d2 Russ W. Knize 2013-04-07 387 lower_file = esdfs_lower_file(file); 1704af1484c6d2 Russ W. Knize 2013-04-07 388 if (!lower_file->f_op->read_iter) { 1704af1484c6d2 Russ W. Knize 2013-04-07 389 err = -EINVAL; 1704af1484c6d2 Russ W. Knize 2013-04-07 390 goto out; 1704af1484c6d2 Russ W. Knize 2013-04-07 391 } 1704af1484c6d2 Russ W. Knize 2013-04-07 392 1704af1484c6d2 Russ W. Knize 2013-04-07 393 get_file(lower_file); /* prevent lower_file from being released */ 1704af1484c6d2 Russ W. Knize 2013-04-07 394 iocb->ki_filp = lower_file; 1704af1484c6d2 Russ W. Knize 2013-04-07 395 err = lower_file->f_op->read_iter(iocb, iter); 1704af1484c6d2 Russ W. Knize 2013-04-07 396 iocb->ki_filp = file; 1704af1484c6d2 Russ W. Knize 2013-04-07 397 fput(lower_file); 1704af1484c6d2 Russ W. Knize 2013-04-07 398 /* update upper inode atime as needed */ 1704af1484c6d2 Russ W. Knize 2013-04-07 399 if (err >= 0 || err == -EIOCBQUEUED) 1704af1484c6d2 Russ W. Knize 2013-04-07 400 fsstack_copy_attr_atime(file->f_path.dentry->d_inode, 1704af1484c6d2 Russ W. Knize 2013-04-07 401 file_inode(lower_file)); 1704af1484c6d2 Russ W. Knize 2013-04-07 402 out: 1704af1484c6d2 Russ W. Knize 2013-04-07 403 return err; 1704af1484c6d2 Russ W. Knize 2013-04-07 404 } 1704af1484c6d2 Russ W. Knize 2013-04-07 405 1704af1484c6d2 Russ W. Knize 2013-04-07 406 /* 1704af1484c6d2 Russ W. Knize 2013-04-07 407 * Wrapfs write_iter, redirect modified iocb to lower write_iter 1704af1484c6d2 Russ W. Knize 2013-04-07 408 */ 1704af1484c6d2 Russ W. Knize 2013-04-07 409 ssize_t 1704af1484c6d2 Russ W. Knize 2013-04-07 @410 esdfs_write_iter(struct kiocb *iocb, struct iov_iter *iter) 1704af1484c6d2 Russ W. Knize 2013-04-07 411 { 1704af1484c6d2 Russ W. Knize 2013-04-07 412 int err; 1704af1484c6d2 Russ W. Knize 2013-04-07 413 struct file *file = iocb->ki_filp, *lower_file; 1704af1484c6d2 Russ W. Knize 2013-04-07 414 1704af1484c6d2 Russ W. Knize 2013-04-07 415 lower_file = esdfs_lower_file(file); 1704af1484c6d2 Russ W. Knize 2013-04-07 416 if (!lower_file->f_op->write_iter) { 1704af1484c6d2 Russ W. Knize 2013-04-07 417 err = -EINVAL; 1704af1484c6d2 Russ W. Knize 2013-04-07 418 goto out; 1704af1484c6d2 Russ W. Knize 2013-04-07 419 } 1704af1484c6d2 Russ W. Knize 2013-04-07 420 1704af1484c6d2 Russ W. Knize 2013-04-07 421 get_file(lower_file); /* prevent lower_file from being released */ 1704af1484c6d2 Russ W. Knize 2013-04-07 422 iocb->ki_filp = lower_file; 1704af1484c6d2 Russ W. Knize 2013-04-07 423 err = lower_file->f_op->write_iter(iocb, iter); 1704af1484c6d2 Russ W. Knize 2013-04-07 424 iocb->ki_filp = file; 1704af1484c6d2 Russ W. Knize 2013-04-07 425 fput(lower_file); 1704af1484c6d2 Russ W. Knize 2013-04-07 426 /* update upper inode times/sizes as needed */ 1704af1484c6d2 Russ W. Knize 2013-04-07 427 if (err >= 0 || err == -EIOCBQUEUED) { 1704af1484c6d2 Russ W. Knize 2013-04-07 428 fsstack_copy_inode_size(file->f_path.dentry->d_inode, 1704af1484c6d2 Russ W. Knize 2013-04-07 429 file_inode(lower_file)); 1704af1484c6d2 Russ W. Knize 2013-04-07 430 fsstack_copy_attr_times(file->f_path.dentry->d_inode, 1704af1484c6d2 Russ W. Knize 2013-04-07 431 file_inode(lower_file)); 1704af1484c6d2 Russ W. Knize 2013-04-07 432 } 1704af1484c6d2 Russ W. Knize 2013-04-07 433 out: 1704af1484c6d2 Russ W. Knize 2013-04-07 434 return err; 1704af1484c6d2 Russ W. Knize 2013-04-07 435 } 1704af1484c6d2 Russ W. Knize 2013-04-07 436 :::::: The code at line 382 was first introduced by commit :::::: 1704af1484c6d2ad8e4452ecedc02acf5b764136 CHROMIUM: fs: Import esdfs code :::::: TO: Russ W. Knize <Russ.Knize(a)motorola.com&gt; :::::: CC: Guenter Roeck <groeck(a)chromium.org&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org