On Wed 28-06-23 21:20:11, Zhihao Cheng wrote: > Running generic/475(filesystem consistent tests after power cut) could > easily trigger unattached inode error while doing fsck: > Unattached zero-length inode 39405. Clear? no > > Unattached inode 39405 > Connect to /lost+found? no > > Above inconsistence is caused by following process: > P1 P2 > ext4_create > inode = ext4_new_inode_start_handle // itable records nlink=1 > ext4_add_nondir > err = ext4_add_entry // ENOSPC > ext4_append > ext4_bread > ext4_getblk > ext4_map_blocks // returns ENOSPC > drop_nlink(inode) // won't be updated into disk inode > ext4_orphan_add(handle, inode) > ext4_orphan_file_add > ext4_journal_stop(handle) > jbd2_journal_commit_transaction // commit success > >> power cut << > ext4_fill_super > ext4_load_and_init_journal // itable records nlink=1 > ext4_orphan_cleanup > ext4_process_orphan > if (inode->i_nlink) // true, inode won't be deleted > > Then, allocated inode will be reserved on disk and corresponds to no > dentries, so e2fsck reports 'unattached inode' problem. > > The problem won't happen if orphan file feature is disabled, because > ext4_orphan_add() will update disk inode in orphan list mode. There > are several places not updating disk inode while putting inode into > orphan area, such as ext4_add_nondir(), ext4_symlink() and whiteout > in ext4_rename(). Fix it by updating inode into disk in all error > branches of these places. > > Link: https://bugzilla.kernel.org/show_bug.cgi?id=217605 > Fixes: 02f310fcf47f ("ext4: Speedup ext4 orphan inode handling") > Signed-off-by: Zhihao Cheng <chengzhihao1@xxxxxxxxxx> Nice catch. Thanks for fixing this. Feel free to add: Reviewed-by: Jan Kara <jack@xxxxxxx> Honza > --- > fs/ext4/namei.c | 3 +++ > 1 file changed, 3 insertions(+) > > diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c > index 0caf6c730ce3..6bcc3770ee19 100644 > --- a/fs/ext4/namei.c > +++ b/fs/ext4/namei.c > @@ -2799,6 +2799,7 @@ static int ext4_add_nondir(handle_t *handle, > return err; > } > drop_nlink(inode); > + ext4_mark_inode_dirty(handle, inode); > ext4_orphan_add(handle, inode); > unlock_new_inode(inode); > return err; > @@ -3436,6 +3437,7 @@ static int ext4_symlink(struct mnt_idmap *idmap, struct inode *dir, > > err_drop_inode: > clear_nlink(inode); > + ext4_mark_inode_dirty(handle, inode); > ext4_orphan_add(handle, inode); > unlock_new_inode(inode); > if (handle) > @@ -4021,6 +4023,7 @@ static int ext4_rename(struct mnt_idmap *idmap, struct inode *old_dir, > ext4_resetent(handle, &old, > old.inode->i_ino, old_file_type); > drop_nlink(whiteout); > + ext4_mark_inode_dirty(handle, whiteout); > ext4_orphan_add(handle, whiteout); > } > unlock_new_inode(whiteout); > -- > 2.39.2 > -- Jan Kara <jack@xxxxxxxx> SUSE Labs, CR
