On Thu, Oct 14, 2021 at 12:54:14PM +0000, Rantala, Tommi T. (Nokia - FI/Espoo) wrote:

Hi,

I'm seeing these i_reserved_data_blocks not cleared! messages when using ext4
with nodelalloc, message added in:

  commit 6fed83957f21eff11c8496e9f24253b03d2bc1dc
  Author: Jeffle Xu [off-list ref]
  Date:   Mon Aug 23 14:13:58 2021 +0800

      ext4: fix reserved space counter leakage

I can quickly reproduce in 5.15.0-rc5-00041-g348949d9a444 by doing some
filesystem I/O while toggling delalloc:


while true; do mount -o remount,nodelalloc /; sleep 1; mount -o remount,delalloc /; sleep 1; done &
git clone linux xxx; rm -rf xxx

If I understand correctly, switching such option implies
sync inodes to write back exist delayed allocation blocks.

At a glance I don't find it. Yet no test actually.

Thanks,
Gao Xiang

[  222.928341] EXT4-fs (vdb1): re-mounted. Opts: delalloc. Quota mode: disabled.
[  223.932516] EXT4-fs (vdb1): re-mounted. Opts: nodelalloc. Quota mode: disabled.
[  224.183741] EXT4-fs (vdb1): Inode 2885482 (000000008e814f64): i_reserved_data_blocks (2) not cleared!
[  224.185064] EXT4-fs (vdb1): Inode 2885478 (00000000862b48ad): i_reserved_data_blocks (2) not cleared!
[  224.186434] EXT4-fs (vdb1): Inode 2885474 (00000000a20bdd95): i_reserved_data_blocks (7) not cleared!
[  224.187649] EXT4-fs (vdb1): Inode 2885476 (00000000028005e1): i_reserved_data_blocks (2) not cleared!
[  224.189016] EXT4-fs (vdb1): Inode 2885475 (0000000025d9617d): i_reserved_data_blocks (2) not cleared!
[  224.190370] EXT4-fs (vdb1): Inode 2885480 (00000000d0722d90): i_reserved_data_blocks (7) not cleared!
[  224.191732] EXT4-fs (vdb1): Inode 2885481 (000000009b50d6cb): i_reserved_data_blocks (1) not cleared!
[  224.193093] EXT4-fs (vdb1): Inode 2885472 (00000000fe907f54): i_reserved_data_blocks (1) not cleared!
[  227.946984] EXT4-fs: 9213 callbacks suppressed
[  227.946989] EXT4-fs (vdb1): re-mounted. Opts: nodelalloc. Quota mode: disabled.


-Tommi