Cannot mount 3.5 format made from mkreiserfs

[Glenn Washburn]

The following commands on Ubuntu Impish live cd reproduce the issue:

truncate -s 256M test.reiser_old.img
mkfs.reiserfs --format=3.5 -b 512 -l 'g;/éт 莭😁' -q test.reiser_old.img
sudo mount -t reiserfs test.reiser_old.img /media/tmp2

The dmesg log shows:
[298084.049115] loop14: detected capacity change from 0 to 524288
[298084.077838] REISERFS (device loop14): found reiserfs format "3.5" with standard journal
[298084.077850] REISERFS (device loop14): using ordered data mode
[298084.077851] reiserfs: using flush barriers
[298084.077893] REISERFS (device loop14): journal params: device loop14, size 3965, journal first block 130, max trans len 128, max batch 112, max commit age 30, max trans age 30
[298084.077993] REISERFS (device loop14): checking transaction log (loop14)
[298084.089579] REISERFS warning: reiserfs-5093 is_leaf: item entry count seems wrong *3.5*[1 2 0(1) DIR], item_len 35, item_location 445, free_space(entry_count) 2
[298084.089584] REISERFS error (device loop14): vs-5150 search_by_key: invalid format found in block 4097. Fsck?
[298084.089588] REISERFS (device loop14): Remounting filesystem read-only
[298084.089590] REISERFS error (device loop14): vs-13070 reiserfs_read_locked_inode: i/o failure occurred trying to find stat data of [1 2 0x0 SD]
[298084.089594] REISERFS (device loop14): Using r5 hash to sort names
[298084.089596] REISERFS (device loop14): using 3.5.x disk format

I'm not sure if this is a mkreiserfs issue or a kernel issue, but I expect the filesystem to be mounted.

ubuntu@ubuntu:~$ lsb_release -rd
Description: Ubuntu Impish Indri (development branch)
Release: 21.10

[Glenn Washburn (crass)]

Looks like the "-q" option also silences errors (wth?). Without "-q" option mkfs.reiserfs fails complaining that test.reiser_old.img is not a block device.

Running the following, also errors:
LOOPDEV=$(losetup --show -f test.reiser_old.img)
mkfs.reiserfs --format=3.5 -b 512 -l 'g;/éт 莭😁' "$LOOPDEV"

Outputting this message: "Block sizes smaller than 4k are not supported."

This contradicts the manpage, which says that block sizes may be between 512 and 8192. But this explains why the mount is having issues.