Hello
I am experiencing a weird and unexpected issue. When archiving a sparse
file virtual disk and file-system that is Reiser4, with the `tar -S`
option accordingly, to actually keep the sparse, I get a corrupted
file-system as a result. This does not happen when the Reiser4 sparse
file lives on EXT4, don't worry. But it happens on GFS2 *1 and my guess
is that it is not something that is supposed to happen. I am not sure
it's a bug, and even so, I am not sure whether it affects Reiser4 --OR--
Redhat GFS2. I ping here at Reiser4 first, to have your advise.
Here's how to reproduce. On a GFS2 file-system, creating a raw sparse
file and a Reiser4 file-system on it.
dd if=/dev/zero of=dummy.reiser4 bs=1G count=0 seek=1
mkfs.reiser4 -fy dummy.reiser4
fsck.reiser4 -y dummy.reiser4
The result is fine, as expected.
*******************************************************************
This is an EXPERIMENTAL version of fsck.reiser4. Read README first.
*******************************************************************
Fscking the dummy.reiser4 block device.
Will check the consistency of the Reiser4 SuperBlock.
Will check the consistency of the Reiser4 FileSystem.
***** fsck.reiser4 started at Fri Sep 18 09:22:01 2020
Reiser4 fs was detected on dummy.reiser4.
Master super block (16):
magic: ReIsEr4
blksize: 4096
format: 0x0 (format40)
uuid: 51b8c5a3-ffd3-4528-9d0b-d5be985231e4
label: <none>
Format super block (17):
plugin: format40
description: Disk-format plugin.
version: 2
magic: ReIsEr40FoRmAt
mkfs id: 0x4934ef80
flushes: 0
blocks: 262144
free blocks: 262107
root block: 23
tail policy: 0x2 (smart)
next oid: 0x10000
file count: 1
tree height: 2
key policy: LARGE
CHECKING THE STORAGE TREE
Read nodes 2
Nodes left in the tree 2
Leaves of them 1, Twigs of them 1
Time interval: Fri Sep 18 09:22:01 2020 - Fri Sep 18 09:22:01 2020
CHECKING EXTENT REGIONS.
Read twigs 1
Time interval: Fri Sep 18 09:22:01 2020 - Fri Sep 18 09:22:01 2020
CHECKING THE SEMANTIC TREE
Found 1 objects (some could be encountered more then once).
Time interval: Fri Sep 18 09:22:01 2020 - Fri Sep 18 09:22:01 2020
***** fsck.reiser4 finished at Fri Sep 18 09:22:01 2020
Closing fs...done
FS is consistent.
Then archiving and extracting it with `-S`.
tar czSf dummy.reiser4.tar.gz dummy.reiser4
rm -f dummy.reiser4
tar xzSf dummy.reiser4.tar.gz
fsck.reiser4 -y dummy.reiser4
and here it comes
*******************************************************************
This is an EXPERIMENTAL version of fsck.reiser4. Read README first.
*******************************************************************
Fscking the dummy.reiser4 block device.
Will check the consistency of the Reiser4 SuperBlock.
Will check the consistency of the Reiser4 FileSystem.
***** fsck.reiser4 started at Fri Sep 18 09:23:23 2020
FSCK: backup.c: 485: repair_backup_open: Only 4 of 5 backup blocks are
found.
Fatal: Failed to open the reiser4 backup.
Fatal: Cannot open the FileSystem on (dummy.reiser4).
1 fatal corruptions were detected in SuperBlock. Run with --build-sb
option to fix them.
What angle should I take to this problem?
Thank you
*1 https://en.wikipedia.org/wiki/GFS2
--
Pierre-Philipp
