[linux-lvm] LVM thin provisioning on encrypted root unreliable

[kurcze <wannabeachicken@gmail.com>]

Hello everyone,


I can't manage to get thinly provisioned LVM setup to work.

The problem is: I can't get to the decryption prompt to enter a password 
to decrypt root filesystem. It just hangs there.

My Setup:

VG with 3 PVs: 1 SSD, 1 HDD, 1 NVMe SSD

Thin pool in this VG with 2 LVs (for / and /var mountpoints)

both partitions are encrypted using LUKS


I've spent quite a lot of time trying many possible solutions. The worst 
thing is: sometimes it seems to work flawlessly for several boots. These 
moments convince me every time, that the previous solution I tried was 
the correct one and I can happily go on with my life. That is not the 
case. Sometimes it doesn't work the first 3 times (after reboot) and 
then suddenly it does (possibly after some tweaking with kernel 
parameters). I can't recognize any pattern. I can also reboot 3 times 
without doing anything and the 4th time it works.

Unfortunately I'm not a pro in this area and I don't know any way to 
debug it.

I would really appreciate the help. I would also gladly provide any 
additional information or command output. Following files might be helpful:

1. dmesg output from initramfs prompt (with Call Trace)

https://pastebin.com/HJkSixCs

2. journal output during shutdown (not cleanly unmounted stuff)

https://pastebin.com/2exWgbze

3. lsblk output

https://pastebin.com/gHttQZH2

4. grepped lsinitramfs with some relevant files

https://pastebin.com/RV1A55MQ

5. lvs with devices

https://pastebin.com/KUv7iiM4


Best regards,

kurcze