Hi Dominique, kernel test robot noticed the following build warnings: url: https://github.com/intel-lab-lkp/linux/commits/Dominique-Martinet/fs-split-off-vfs_getdents-function-of-getdents64-syscall/20230510-185542 base: 58390c8ce1bddb6c623f62e7ed36383e7fa5c02f patch link: https://lore.kernel.org/r/20230422-uring-getdents-v2-4-2db1e37dc55e%40codewreck.org patch subject: [PATCH v2 4/6] kernfs: implement readdir FMODE_NOWAIT config: i386-randconfig-m021 (https://download.01.org/0day-ci/archive/20230511/202305110647.eSnSEulg-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-12) 11.3.0 If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Reported-by: Dan Carpenter <error27@xxxxxxxxx> | Link: https://lore.kernel.org/r/202305110647.eSnSEulg-lkp@xxxxxxxxx/ smatch warnings: fs/kernfs/dir.c:1863 kernfs_fop_readdir() warn: inconsistent returns '&root->kernfs_rwsem'. vim +1863 fs/kernfs/dir.c c637b8acbe079e Tejun Heo 2013-12-11 1815 static int kernfs_fop_readdir(struct file *file, struct dir_context *ctx) fd7b9f7b9776b1 Tejun Heo 2013-11-28 1816 { fd7b9f7b9776b1 Tejun Heo 2013-11-28 1817 struct dentry *dentry = file->f_path.dentry; 319ba91d352a74 Shaohua Li 2017-07-12 1818 struct kernfs_node *parent = kernfs_dentry_node(dentry); 324a56e16e44ba Tejun Heo 2013-12-11 1819 struct kernfs_node *pos = file->private_data; 393c3714081a53 Minchan Kim 2021-11-18 1820 struct kernfs_root *root; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1821 const void *ns = NULL; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1822 fd7b9f7b9776b1 Tejun Heo 2013-11-28 1823 if (!dir_emit_dots(file, ctx)) fd7b9f7b9776b1 Tejun Heo 2013-11-28 1824 return 0; 393c3714081a53 Minchan Kim 2021-11-18 1825 393c3714081a53 Minchan Kim 2021-11-18 1826 root = kernfs_root(parent); a551138c4b3b9f Dominique Martinet 2023-05-10 1827 if (ctx->flags & DIR_CONTEXT_F_NOWAIT) { a551138c4b3b9f Dominique Martinet 2023-05-10 1828 if (!down_read_trylock(&root->kernfs_rwsem)) a551138c4b3b9f Dominique Martinet 2023-05-10 1829 return -EAGAIN; a551138c4b3b9f Dominique Martinet 2023-05-10 1830 } else { 393c3714081a53 Minchan Kim 2021-11-18 1831 down_read(&root->kernfs_rwsem); a551138c4b3b9f Dominique Martinet 2023-05-10 1832 } fd7b9f7b9776b1 Tejun Heo 2013-11-28 1833 324a56e16e44ba Tejun Heo 2013-12-11 1834 if (kernfs_ns_enabled(parent)) c525aaddc366df Tejun Heo 2013-12-11 1835 ns = kernfs_info(dentry->d_sb)->ns; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1836 c637b8acbe079e Tejun Heo 2013-12-11 1837 for (pos = kernfs_dir_pos(ns, parent, ctx->pos, pos); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1838 pos; c637b8acbe079e Tejun Heo 2013-12-11 1839 pos = kernfs_dir_next_pos(ns, parent, ctx->pos, pos)) { adc5e8b58f4886 Tejun Heo 2013-12-11 1840 const char *name = pos->name; 364595a6851bf6 Jeff Layton 2023-03-30 1841 unsigned int type = fs_umode_to_dtype(pos->mode); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1842 int len = strlen(name); 67c0496e87d193 Tejun Heo 2019-11-04 1843 ino_t ino = kernfs_ino(pos); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1844 adc5e8b58f4886 Tejun Heo 2013-12-11 1845 ctx->pos = pos->hash; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1846 file->private_data = pos; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1847 kernfs_get(pos); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1848 393c3714081a53 Minchan Kim 2021-11-18 1849 up_read(&root->kernfs_rwsem); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1850 if (!dir_emit(ctx, name, len, ino, type)) fd7b9f7b9776b1 Tejun Heo 2013-11-28 1851 return 0; 393c3714081a53 Minchan Kim 2021-11-18 1852 down_read(&root->kernfs_rwsem); ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Needs to be deleted. a551138c4b3b9f Dominique Martinet 2023-05-10 1853 if (ctx->flags & DIR_CONTEXT_F_NOWAIT) { a551138c4b3b9f Dominique Martinet 2023-05-10 1854 if (!down_read_trylock(&root->kernfs_rwsem)) a551138c4b3b9f Dominique Martinet 2023-05-10 1855 return 0; It's a bit strange the this doesn't return -EAGAIN; a551138c4b3b9f Dominique Martinet 2023-05-10 1856 } else { a551138c4b3b9f Dominique Martinet 2023-05-10 1857 down_read(&root->kernfs_rwsem); a551138c4b3b9f Dominique Martinet 2023-05-10 1858 } fd7b9f7b9776b1 Tejun Heo 2013-11-28 1859 } 393c3714081a53 Minchan Kim 2021-11-18 1860 up_read(&root->kernfs_rwsem); fd7b9f7b9776b1 Tejun Heo 2013-11-28 1861 file->private_data = NULL; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1862 ctx->pos = INT_MAX; fd7b9f7b9776b1 Tejun Heo 2013-11-28 @1863 return 0; fd7b9f7b9776b1 Tejun Heo 2013-11-28 1864 } -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests
