Unable to mount btrfs subvol with a new kernel

[mailcimbi <mailcimbi@gmail.com>]

Dear List,

I have two btrfs subvol in my fileset. I can mount it with lubuntu 18.04 
but unable to mount with a newer version. Also unable to mount it when I 
upgrade to the latest 18.04. By the way upgrading to 20.04 (using the 
older kernel after upgrading to the latest 18.04) and starting it with 
an older kernel it is working.

I can reproduce it. Starting with lubuntu 21.04 live cd: unable to 
mount. Starting with lubuntu 18.04.2 live cd: I can mount it.

Here are the results:
lubuntu 18.04
root@lubuntu:~# uname -a
Linux lubuntu 4.18.0-15-generic #16~18.04.1-Ubuntu SMP Thu Feb 7 
14:06:04 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
mounted btrfs with live cd
root@lubuntu:~# mount -t btrfs -o rw,subvol=@ /dev/sda3 /mnt
/dev/sda3        28G   14G   12G  55% /mnt
root@lubuntu:~# mount -t btrfs -o rw,subvol=@home /dev/sda3 /mnt/home
/dev/sda3        28G   14G   12G  55% /mnt/home
root@lubuntu:~# btrfs version
btrfs-progs v4.15.1


lubuntu 20.04
root@lubuntu:~# uname -a
Linux lubuntu 5.4.0-42-generic #46-Ubuntu SMP Fri Jul 10 00:24:02 UTC 
2020 x86_64 x86_64 x86_64 GNU/Linux
root@lubuntu:~# mount -t btrfs -o rw,subvol=@ /dev/sda3 /mnt
mount: /mnt: wrong fs type, bad option, bad superblock on /dev/sda3, 
missing codepage or helper program, or other error.
root@lubuntu:~# btrfs version
btrfs-progs v5.10.1

 From the log it seems there is/are corrupt leaf(s)
[ 3231.406914] BTRFS critical (device sda3): corrupt leaf: 
block=1045233664 slot=17 extent bytenr=20209664 len=8192 invalid 
generation, have 895434752 expect (0, 3790778]
[ 3231.406922] BTRFS error (device sda3): block=1045233664 read time 
tree block corruption detected
[ 3231.406971] BTRFS error (device sda3): failed to read block groups: -5
[ 3231.409566] BTRFS error (device sda3): open_ctree failed


Do you have an idea how to solve it. When I try to check the subvols 
with btrfs check all seems to be fine in 18.04.

Thank you in advance.
Miklos