Hi NeilBrown, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on hnaz-mm/master] [also build test WARNING on axboe-block/for-next konis-nilfs2/upstream xfs-linux/for-next linus/master v5.16-rc5] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/NeilBrown/Remove-some-congested-... base: https://github.com/hnaz/linux-mm master config: arc-randconfig-r015-20211213 (https://download.01.org/0day-ci/archive/20211213/202112131323.fj31o6EV-lk...) compiler: arceb-elf-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 # https://github.com/0day-ci/linux/commit/41802b6debbde3d5553a8067ba2deb203... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review NeilBrown/Remove-some-congested-tests/20211213-121653 git checkout 41802b6debbde3d5553a8067ba2deb2035e6da6e # 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=arc SHELL=/bin/bash fs/ext2/ 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 >>): fs/ext2/ialloc.c: In function 'ext2_preread_inode': 173 | struct backing_dev_info *bdi; | ^~~ vim +/bdi +173 fs/ext2/ialloc.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 154 ^1da177e4c3f41 Linus Torvalds 2005-04-16 155 /* ^1da177e4c3f41 Linus Torvalds 2005-04-16 156 * We perform asynchronous prereading of the new inode's inode block when ^1da177e4c3f41 Linus Torvalds 2005-04-16 157 * we create the inode, in the expectation that the inode will be written ^1da177e4c3f41 Linus Torvalds 2005-04-16 158 * back soon. There are two reasons: ^1da177e4c3f41 Linus Torvalds 2005-04-16 159 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 160 * - When creating a large number of files, the async prereads will be ^1da177e4c3f41 Linus Torvalds 2005-04-16 161 * nicely merged into large reads ^1da177e4c3f41 Linus Torvalds 2005-04-16 162 * - When writing out a large number of inodes, we don't need to keep on ^1da177e4c3f41 Linus Torvalds 2005-04-16 163 * stalling the writes while we read the inode block. ^1da177e4c3f41 Linus Torvalds 2005-04-16 164 * ^1da177e4c3f41 Linus Torvalds 2005-04-16 165 * FIXME: ext2_get_group_desc() needs to be simplified. ^1da177e4c3f41 Linus Torvalds 2005-04-16 166 */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 167 static void ext2_preread_inode(struct inode *inode) ^1da177e4c3f41 Linus Torvalds 2005-04-16 168 { ^1da177e4c3f41 Linus Torvalds 2005-04-16 169 unsigned long block_group; ^1da177e4c3f41 Linus Torvalds 2005-04-16 170 unsigned long offset; ^1da177e4c3f41 Linus Torvalds 2005-04-16 171 unsigned long block; ^1da177e4c3f41 Linus Torvalds 2005-04-16 172 struct ext2_group_desc * gdp; ^1da177e4c3f41 Linus Torvalds 2005-04-16 @173 struct backing_dev_info *bdi; ^1da177e4c3f41 Linus Torvalds 2005-04-16 174 de1414a654e66b Christoph Hellwig 2015-01-14 175 bdi = inode_to_bdi(inode); ^1da177e4c3f41 Linus Torvalds 2005-04-16 176 ^1da177e4c3f41 Linus Torvalds 2005-04-16 177 block_group = (inode->i_ino - 1) / EXT2_INODES_PER_GROUP(inode->i_sb); ef2fb67989d30f Eric Sandeen 2007-10-16 178 gdp = ext2_get_group_desc(inode->i_sb, block_group, NULL); ^1da177e4c3f41 Linus Torvalds 2005-04-16 179 if (gdp == NULL) ^1da177e4c3f41 Linus Torvalds 2005-04-16 180 return; ^1da177e4c3f41 Linus Torvalds 2005-04-16 181 ^1da177e4c3f41 Linus Torvalds 2005-04-16 182 /* ^1da177e4c3f41 Linus Torvalds 2005-04-16 183 * Figure out the offset within the block group inode table ^1da177e4c3f41 Linus Torvalds 2005-04-16 184 */ ^1da177e4c3f41 Linus Torvalds 2005-04-16 185 offset = ((inode->i_ino - 1) % EXT2_INODES_PER_GROUP(inode->i_sb)) * ^1da177e4c3f41 Linus Torvalds 2005-04-16 186 EXT2_INODE_SIZE(inode->i_sb); ^1da177e4c3f41 Linus Torvalds 2005-04-16 187 block = le32_to_cpu(gdp->bg_inode_table) + ^1da177e4c3f41 Linus Torvalds 2005-04-16 188 (offset >> EXT2_BLOCK_SIZE_BITS(inode->i_sb)); ^1da177e4c3f41 Linus Torvalds 2005-04-16 189 sb_breadahead(inode->i_sb, block); ^1da177e4c3f41 Linus Torvalds 2005-04-16 190 } ^1da177e4c3f41 Linus Torvalds 2005-04-16 191 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org