On Wed, Jun 12, 2019 at 02:40:18PM -0600, Andreas Dilger wrote: > On Jun 12, 2019, at 8:07 AM, Rasmus Villemoes <linux@xxxxxxxxxxxxxxxxxx> wrote: > > > > Doing a forced check on an ext4 file system with inline_data results in > > lots of warnings - and I think answering yes to "fixing" those would > > actually corrupt the fs. > > Rasmus, > This definitely seems like a bug in e2fsck. It isn't totally surprising, since > the inline_data feature is not widely used. We are currently investigating using > it for regular files, but it doesn't seem worthwhile for directories to me. It looks like the problem is the combination of large_dir and inline_data, and it does look like the problem is in e2fsck (as opposed to the kernel). Large_dir is a new feature (even newer than inline_data, and it looks like the support for large_dir didn't handle the combination with inline_data correctly). - Ted # mke2fs -t ext4 -O inline_data -Fq /tmp/ext4.img 1G /tmp/ext4.img contains a ext4 file system last mounted on Wed Jun 12 21:47:25 2019 # mount /tmp/ext4.img /mnt ; mkdir /mnt/aa ; umount /mnt # e2fsck -fn /tmp/ext4.img e2fsck 1.45.2 (27-May-2019) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity Pass 4: Checking reference counts Pass 5: Checking group summary information /tmp/ext4.img: 12/65536 files (0.0% non-contiguous), 12954/262144 blocks ### So everything is fine with just inline_data, but when you ### enable the large_dir features, and rerun e2fsck.... # debugfs -w -R "features large_dir" /tmp/ext4.img debugfs 1.45.2 (27-May-2019) Filesystem features: has_journal ext_attr resize_inode dir_index filetype extent 64bit flex_bg large_dir inline_data sparse_super large_file huge_file dir_nlink extra_isize metadata_csum # e2fsck -fn /tmp/ext4.img e2fsck 1.45.2 (27-May-2019) Pass 1: Checking inodes, blocks, and sizes Pass 2: Checking directory structure Pass 3: Checking directory connectivity '..' in /aa (12) is <The NULL inode> (0), should be / (2). Fix? no Pass 4: Checking reference counts Inode 2 ref count is 4, should be 3. Fix? no Inode 12 ref count is 2, should be 1. Fix? no Pass 5: Checking group summary information /tmp/ext4.img: ********** WARNING: Filesystem still has errors ********** /tmp/ext4.img: 12/65536 files (0.0% non-contiguous), 12954/262144 blocks
